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Dim the Glare: Upgrade Your Drive with Auto-Dimming Mirrors

Auto-Dimming Mirrors: An Innovative Technology to Enhance Driving Safety

Have you ever faced difficulty while driving at night due to the glare from the headlights of other cars? Or, have you ever been blinded by the high beams of an approaching vehicle?

If yes, then you must have realized the importance of having a clear view while driving and how it can help prevent accidents. To address this concern, the automotive industry has come up with an innovative technology known as auto-dimming mirrors.

In this article, we will discuss what auto-dimming mirrors are, how they work, and their advantages and disadvantages.to Auto-Dimming Mirrors

Auto-dimming mirrors are advanced technological devices that adjust the mirror’s reflective surface based on the amount of light it detects. The auto-dimming mirror is connected to a sensor on the dashboard that detects the level of light around the vehicle.

The mirror automatically darkens when it detects bright light, such as headlights or sunlight, to prevent glare and reduce strain on the driver’s eyes. How Does Auto-Dimming Mirrors Work?

Auto-dimming mirrors use two types of technologies to reduce glare: electrochromism and photovoltaic. Electrochromism is the method used in the majority of auto-dimming mirrors.

This technology works through a thin layer of electrochromic gel. The gel sits between the two layers of reflective glass and turns darker when an electrical current is applied to it.

Sensors on the back of the mirror detect the amount of light, and the electrical current is adjusted, causing the gel to darken. Photovoltaic technology is a newer type of technology used in a few auto-dimming mirrors.

This technology uses a layer of photochromic gel in place of electrochromic gel. The photochromic gel reacts with the ultraviolet rays from the sun to darken, and the system does not require any electrical input to function.

Advantages of Auto-Dimming Mirrors

There are several advantages to using auto-dimming mirrors, including:

1. Enhanced Safety: Auto-dimming mirrors reduce glare from bright lights and ensure that the driver doesn’t lose their visibility, especially at night.

2. Improved Visibility: The technology adjusts the reflective surface, providing better visibility and reducing eye strain, which is beneficial for drivers who frequently work late nights or under intense sunlight.

3. Hands-Free Functionality: Auto-dimming mirrors operate automatically, making them safer than manual mirrors as they do not require any manual adjustment.

Disadvantages of Auto-Dimming Mirrors

Despite all the benefits of auto-dimming mirrors, there are certain disadvantages:

1. Higher Price: Auto-dimming mirrors are expensive compared to conventional mirrors.

2. Possible Malfunction: Auto-dimming mirrors may malfunction if the electrical system is not functioning correctly, which may cause the mirror to become degraded, which, in turn, results in delayed recognition of fast-moving objects, leading to the possibility of an accident.

Automakers Requiring Auto-Dimming Mirrors

Since auto-dimming mirrors are expensive, some drivers tend to overlook their benefits. However, some automakers make auto-dimming mirrors standard or optional with their vehicles.

The list of automakers includes Audi, BMW, Cadillac, Chevrolet, Ford, GMC, Honda, Infiniti, Kia, Land Rover, Lexus, Mazda, Mercedes-Benz, Nissan, Porsche, Subaru, Tesla, Toyota, and Volvo.


Auto-dimming mirrors are a revolutionary technology that enhances driver’s visibility in low light conditions, particularly at night. They reduce eye strain and create a comfortable driving experience.

Although the technology comes with additional costs, some automakers make auto-dimming mirrors standard, which makes the cars even more attractive to drivers who prioritize safety. We hope this article has addressed your queries on auto-dimming mirrors and convinced you to consider them for your future car options.

The History of Auto-Dimming Mirrors

The invention of auto-dimming mirrors dates back to the early 1900s. At that time, drivers had to adjust the angle of the mirror to avoid the glare of bright lights at night.

However, the process of manual readjustment was inconvenient and dangerous because it required the driver to take their eyes off the road. The early solutions did not involve sophisticated technology, but they set the foundation for the modern auto-dimming mirrors that we have today.

The first auto-dimming mirrors were inspired by the polarizing filters used in photography. Polarization is a property of some transparent materials that allows them to block one polarization direction while transmitting the other.

By arranging two polarizing filters at right angles to each other, the intensity of the transmitted light can be controlled. The principle was applied to mirrors, where a layer of film containing millions of microscopic dichroic particles was inserted in between two glass plates.

The film and glass combination acted like a pair of polarizers. When the light came from behind, it was polarized in a specific direction.

Therefore, when it reached the mirror, it passed through the first polarizing glass with low intensity. This polarized light directly hit the layer of film, which then directed the light through the second polarizing glass on the front of the mirror, which had a high absorbance.

The result is the suppression of unwanted glare seen in the rearview mirror. While the early versions of auto-dimming mirrors did a good job of reducing glare, they were expensive.

They were first introduced in the upscale cars of the 1930s but were installed primarily in extravagant cars. The technology stayed limited till the 1980s when electronic sensors became available.

With the advent of electronic control systems, auto-dimming technology became more popularized because sensors no longer required elaborate mechanical adjustments. The first electronic control automatic-dimming mirror came out in 1980.

Toyota introduced this tech in their Toyota Crown Majesta vehicles in Japan. The innovation included a sensor, control circuit, and a gallium arsenide photodiode.

The gallium arsenide photodiode helped measure the brightness of light falling on the rearview mirror. When too much light reflecting onto the mirror, the sensor sent a signal to the control circuit shutting off the electricity to tiny crystals sandwiched between the mirror’s glass layers, giving the mirror its unique tint.

The crystal’s polarization would change when it received an electronic signal from control systems. The mirror’s electrical system could produce a variable electric current that could adjust the shade of the rearview mirror.

In the same year, General Motors and Gentex, a manufacturer of electro-optic products, introduced automatic-dimming rearview mirrors (ADRM) on Cadillac Seville and Buick Riviera vehicles, as well as the Oldsmobile War. General Motors had collaborated with Gentex, a company that developed optoelectronics and digital display systems.

They created a device capable of mechanically holding a pair of polarizing filters between glasses. The device uses a light-sensitive semiconductor sensor positioned behind the electrochromic mirror.

When light shines on the sensor, an electrical signal is sent to darken the area. When the source of the light is no longer detected, the sensor signals the circuit to restore the tint back to normal.

Today, almost every automaker offers auto-dimming mirrors as either a standard equipment feature or a high-tech option. They have become increasingly affordable, and with innovations in smart technology, they have become more than just a basic safety feature.

How to Manually Adjust an Auto-Dimming Mirror

Auto-dimming mirrors are designed to adjust the reflective surface automatically to reduce glare from headlights and sunlight, providing enhanced visibility to the driver. However, there may be times when an individual wants to adjust the angle of the mirror manually.

Here is how to do it:

1. Find the Adjustment Buttons: Locate the adjustment buttons on the mirror’s bottom or side.

For some mirrors, the buttons may be nestled within the mirror surface, making them almost invisible. 2.

Press the Button: Once the button is found, press it to activate the adjustment mechanism. The system will give an audible click, indicating that it is ready for use.

3. Adjust the Mirror: Manually move the mirror to the desired angle by adjusting the orientation of the glass relative to the rear windshield.

Once the desired angle is achieved, release the button. 4.

Lock the Adjustment: Some mirrors have an auto-lock function while others require the driver to lock it manually. If the mirror’s adjustments are not auto-locked, secure it by pressing and holding the same button used to activate the adjustment mechanism until the mirror clicks into place.

It is crucial to remember that auto-dimming mirrors are designed to automatically adjust on their own, so manually readjusting the mirror often is not necessary. Additionally, auto-dimming mirrors can malfunction, so manual adjustments may be necessary in such incidents.

However, professionally trained technicians should handle such instances to prevent further damage to the mirror’s technology.


Auto-dimming mirrors may have first been introduced in the 1930s, but they have undergone tremendous technological advances to become sophisticated and ubiquitous. The technology helps improve visibility, limiting eye strain and reducing the risks associated with glare and strain-induced fatigue.

The manual adjustment of auto-dimming mirrors is essential knowledge for drivers, particularly in the event of a malfunction.

Common Issues with Auto-Dimming Mirrors

Auto-dimming mirrors offer several benefits such as enhanced visibility, reduced glare, and improved safety. However, like any other technology, they can develop issues that affect the functionality of the mirrors.

Some of the most common problems with auto-dimming mirrors include:

1. Malfunctioning Sensors: Auto-dimming mirrors rely on sensors that monitor the brightness of external light sources.

Sensor malfunction can cause the mirror to darken or brighten excessively. 2.

Electrical Issues: Electrical problems such as loose wire connections can cause auto-dimming mirrors to malfunction. Damage to the electronic control module can also cause the mirrors not to function.

3. Scratches on the Mirror: Scratches can cause the auto-dimming mechanism to malfunction, causing reduced visibility.

4. Depletion of Electrochromic Material: Auto-dimming mirrors contain a thin layer of electrochromic material sandwiched between two sheets of glass.

The depletion of the electrochromic material can cause irreversible damage to the mirror, resulting in permanent dullness. 5.

Defective Electronics: Defective electronics, such as the photochromic gel, can cause problems with auto-dimming mirrors and affect their functionality.

How to Troubleshoot Auto-Dimming Mirror Problems

Auto-dimming mirrors significantly improve the safety and functionality of cars, especially when driving in low-light conditions. However, they can develop issues that need troubleshooting to restore their functionality.

Here are some steps to troubleshoot problems with auto-dimming mirrors:

1. Check the Electrical Connections: Loose wire connections can cause auto-dimming mirrors to malfunction.

Start by ensuring that the wires connecting the mirror to the electronic control module are well-connected, and there are no loose wires or damaged connections. 2.

Inspect the Sensor: The sensor located on the dashboard, near the bottom of the windshield, determines whether the mirror should dim or brighten. Cloudiness or film buildup on the sensor may cause it to malfunction.

Remove any obstruction on the sensor, and clean it up with a clean and dry microfiber cloth. 3.

Check for Scratches or Damage: Scratches or damage to the mirror’s surface can cause the auto-dimming feature to malfunction. Inspect the mirror’s surface for scratches or damage, and assess the extent of the damage.

If the scratches are minor, they can be easily buffed out. However, if the scratches are significant, it may require a professional to replace the mirror.

4. Check the Power Source: Auto-dimming mirrors rely on a power source to function.

Check the power source by testing the electrical component to determine if it is functioning correctly. If the component is not faulty, check the voltage level and ensure it is at the optimal level.

5. Inspect the Electrochromic Material: The electrochromic material in auto-dimming mirrors can be depleted over time, resulting in dullness, making the mirrors less efficient.

Monitor the mirror if it is dull. If the mirror is dull, and the sensors and inputs are alright, it may require a full replacement.


Auto-dimming mirrors are sophisticated technological devices that prevent road accidents by enhancing visibility while driving. However, like any other technology, they may develop problems that require troubleshooting to restore their functionality.

By troubleshooting these problems, drivers can maintain safety on the road and ensure that their auto-dimming mirrors are functioning optimally.

Other Features That May Be Integrated with Auto-Dimming Mirrors

Auto-dimming mirrors have come a long way since their inception, evolving into advanced technological devices that offer more than just glare reduction. With advancements in automotive technology, manufacturers have integrated other features with auto-dimming mirrors to enhance the overall driving experience.

Here are some additional features that may be integrated with auto-dimming mirrors:

1. Digital Compass: Some auto-dimming mirrors are equipped with a built-in digital compass.

This feature displays the direction in which the vehicle is heading, providing drivers with real-time information on their navigation. The digital compass can be a useful tool, especially when exploring unfamiliar areas or trying to find a specific location.

2. Homelink Systems: Homelink systems are integrated into some auto-dimming mirrors, allowing drivers to control various electronic devices in their homes.

With Homelink, drivers can remotely operate garage doors, gates, and exterior lighting systems, eliminating the need for multiple remotes or keypads. 3.

Temperature and Compass Display: For added convenience, some auto-dimming mirrors feature displays that show both the outside temperature and the compass direction simultaneously. This information can help drivers make informed decisions about their route or adjust their driving habits based on weather conditions.

4. Rearview Camera Display: Rearview camera systems have become popular safety features in modern vehicles.

Some auto-dimming mirrors are equipped with a digital display that shows the view from the rearview camera. This integration allows drivers to have a clear view of what is behind their vehicle, aiding in parking, reversing, and overall situational awareness.

5. Blind Spot Indicators: Blind spot indicators are designed to warn drivers of vehicles in their blind spots, reducing the risk of accidents during lane changes.

In certain auto-dimming mirrors, these indicators are integrated into the mirror surface itself, making them easily visible without taking the driver’s attention away from the road. 6.

Rain Sensors: Rain sensors detect raindrops on the windshield and automatically activate the windshield wipers. Some auto-dimming mirrors are equipped with rain sensors that work in conjunction with the wiper system, ensuring that wipers are activated at the appropriate speed and interval to maintain optimal visibility in inclement weather.

7. Garage Door Opener Compatibility: In addition to the Homelink system mentioned earlier, some auto-dimming mirrors are compatible with specific brands of garage door openers.

This integration allows drivers to program their mirror to open and close their garage doors with the push of a button, eliminating the need for separate remote controls.

How to Clean Auto-Dimming Mirrors

To maintain proper functionality and optimum visibility, it is essential to regularly clean auto-dimming mirrors. Cleaning these mirrors requires special care due to their sensitive electronic components.

Here’s how to clean auto-dimming mirrors effectively:

1. Gather the Necessary Supplies: To clean auto-dimming mirrors, you will need a microfiber cloth, a mild glass cleaner, and warm water.

2. Turn Off the Auto-Dimming Function: Before cleaning the mirror, ensure that the auto-dimming function is turned off.

This can usually be done by pressing a button or switch dedicated to the mirror’s dimming feature. 3.

Dampen the Microfiber Cloth: Moisten the microfiber cloth with warm water. Avoid using excessive water, as it could damage the electronic components.

4. Clean the Mirror Surface: Gently wipe the mirror surface with the damp microfiber cloth, applying light pressure to remove any dust, smudges, or fingerprints.

Be careful not to apply excessive force or use harsh cleaning agents that could damage the mirror. 5.

Use a Glass Cleaner (Optional): If the mirror requires additional cleaning, you can apply a small amount of mild glass cleaner directly to the microfiber cloth. Avoid spraying the cleaner directly onto the mirror, as the liquid may seep into the mirror housing and damage the electronics.

Wipe the mirror surface in a circular motion, ensuring complete coverage. 6.

Dry the Mirror: After cleaning, use a dry part of the microfiber cloth to gently dry the mirror surface, removing any residual moisture. Make sure the mirror is completely dry before turning the auto-dimming function back on.

7. Inspect for Streaks or Residue: Once the mirror is dry, inspect it for streaks or residue.

If any streaks are present, you can use a clean and dry microfiber cloth to buff the mirror gently until all streaks are removed. Remember to exercise caution while cleaning auto-dimming mirrors to avoid damaging the delicate electronics.

If you notice any persistent issues with the mirror’s performance, it is recommended to consult a professional to assess and resolve the problem.


Auto-dimming mirrors have evolved beyond their primary function of glare reduction. With the integration of other features such as digital compasses, Homelink systems, and rearview camera displays, these mirrors have enhanced the driving experience and improved overall safety.

Cleaning auto-dimming mirrors requires gentle care to avoid damaging the delicate electronic components. By following the recommended cleaning steps, drivers can maintain the functionality and clarity of their auto-dimming mirrors for a safer and more enjoyable driving experience.

Comparing Auto-Dimming Mirrors to Other Types of Mirrors

Mirrors play a vital role in ensuring driver safety and providing a clear view of the road and the surrounding environment. Auto-dimming mirrors have gained popularity due to their unique ability to reduce glare and enhance visibility in challenging lighting conditions.

In this section, we will compare auto-dimming mirrors to other types of mirrors commonly used in vehicles. 1.

Conventional Mirrors:

Conventional mirrors, also known as standard mirrors, are the most basic type of mirror found in vehicles. They consist of a flat or slightly curved reflective surface mounted on the windshield or interior roof panel.

While conventional mirrors are cost-effective and widely used, they lack the advanced functionality of auto-dimming mirrors. They do not have the capability to automatically adjust the reflective surface, making them prone to excessive glare and reduced visibility, especially when faced with bright headlights or direct sunlight.

2. Electrochromic Mirrors:

Electrochromic mirrors are similar to auto-dimming mirrors in functionality, as they both utilize electrochromic technology.

The main difference lies in their application. Auto-dimming mirrors are primarily used as rearview mirrors, while electrochromic mirrors can be integrated into side mirrors as well.

Electrochromic side mirrors darken to reduce glare from vehicles approaching from the rear, enhancing driver visibility and safety. 3.

Blind Spot Mirrors:

Blind spot mirrors are small, convex mirrors attached to the side mirrors of a vehicle. They are designed to eliminate blind spots by providing a wider field of view.

While blind spot mirrors are effective in alerting drivers to vehicles in adjacent lanes, they do not address the issue of glare from headlights or direct sunlight. Their purpose is solely to enhance visibility of other vehicles in the blind spot area.

4. Tinted Mirrors:

Tinted mirrors feature a tinted or colored reflective surface that reduces the intensity of light and glare.

They are commonly used in vehicles to enhance privacy and reduce the amount of light entering the cabin. However, tinted mirrors do not actively adjust their reflective surface based on the surrounding light conditions, making them less effective in reducing glare and maintaining optimal visibility.

Auto-Dimming Mirrors and Safety

Auto-dimming mirrors are not just a convenient feature; they play a crucial role in ensuring driver safety. By reducing glare and enhancing visibility, auto-dimming mirrors contribute to a safer driving experience in the following ways:


Reduction of Eye Strain:

Glare from headlights or direct sunlight can cause eye strain, fatigue, and reduced visibility, increasing the risk of accidents. Auto-dimming mirrors alleviate these issues by automatically adjusting the reflective surface to reduce glare.

This feature allows drivers to focus on the road ahead without straining their eyes, promoting safer and more comfortable driving. 2.

Enhanced Nighttime Visibility:

Driving at night can be challenging due to the increased presence of bright headlights from oncoming vehicles. Auto-dimming mirrors help maintain a clearer view by darkening the reflective surface when exposed to bright lights.

This ensures that the driver’s vision is not compromised by glare, enabling them to detect potential hazards and react promptly. 3.

Improved Visibility in Inclement Weather:

Auto-dimming mirrors also provide improved visibility in adverse weather conditions such as heavy rain, snow, or fog. The mirrors’ ability to reduce glare helps drivers maintain a clear view of the road and surrounding objects, minimizing the chances of accidents caused by reduced visibility.

4. Decreased Distraction:

Glare from headlights or sunlight can be distracting, diverting the driver’s attention from the road.

Auto-dimming mirrors help reduce this distraction by automatically adjusting the reflective surface to minimize glare. This allows drivers to stay focused on the road ahead, enhancing their awareness and response to potential hazards.

5. Prevention of Temporary Vision Impairment:

When directly exposed to bright headlights or sunlight, drivers may experience temporary vision impairment known as the Troxler effect.

This phenomenon causes the eyes to lose sensitivity to dimmer objects, making it difficult to see clearly. Auto-dimming mirrors mitigate the impact of the Troxler effect by reducing the intensity of the light that enters the driver’s eyes, ensuring optimal visibility and preventing temporary vision impairment.


Auto-dimming mirrors offer significant advantages over conventional mirrors and other types of mirrors when it comes to enhancing driver safety. By automatically adjusting the reflective surface to reduce glare, these mirrors alleviate eye strain, improve visibility in low-light conditions, reduce distractions, and prevent temporary vision impairment.

With their advanced technology and safety-focused design, auto-dimming mirrors are an essential feature in modern vehicles, providing drivers with better visibility and promoting a safer driving experience.

The Impact of Auto-Dimming Mirrors on Night-Time Driving

Night-time driving presents a unique set of challenges, including reduced visibility due to the absence of natural light and the presence of bright headlights from oncoming vehicles. However, the inclusion of auto-dimming mirrors in modern vehicles has significantly improved night-time driving safety.

In this section, we will explore the impact of auto-dimming mirrors on night-time driving. 1.

Glare Reduction:

One of the primary benefits of auto-dimming mirrors is their ability to reduce glare from headlights. Excessive glare can be blinding, causing temporary vision impairment and making it difficult to see the road and other essential objects.

Auto-dimming mirrors automatically adjust their reflective surface to dim the intensity of the light that reaches the driver’s eyes, mitigating the effects of glare and enhancing visibility. This reduction in glare allows drivers to maintain a clearer view of the road, ultimately making night-time driving safer.

2. Enhanced Contrast:

Auto-dimming mirrors not only reduce glare but also enhance contrast levels during night-time driving.

By adjusting the reflective surface to optimize the amount of light entering the driver’s eyes, these mirrors create a more balanced lighting environment. This improved contrast enables drivers to distinguish objects and obstacles more easily, facilitating quicker recognition and response, especially in low-light conditions.

3. Reduced Eye Strain:

Driving at night can strain the eyes due to the constant adjustment between brightly lit areas and darker surroundings.

Auto-dimming mirrors help alleviate eye strain by ensuring a consistent level of illumination in the cabin. The mirrors adjust to dim the reflective surface when exposed to bright lights, preventing the eyes from being overwhelmed and fatigued.

This reduction in eye strain promotes a more comfortable driving experience, allowing drivers to stay alert and focused on the road, thus reducing the risk of accidents. 4.

Improved Peripheral Vision:

Auto-dimming mirrors also improve peripheral vision during night-time driving. The mirrors’ ability to reduce glare and maintain optimal visibility extends beyond the direct field of view.

By reducing the impact of bright lights from vehicles approaching from the side or rear, these mirrors enhance peripheral vision, providing drivers with a more comprehensive view of surrounding hazards and increasing their overall situational awareness. 5.

Reduced Distraction:

Glare from headlights can be distracting, diverting the driver’s attention from the road. Auto-dimming mirrors help minimize this distraction by automatically adjusting the reflective surface to dim the glare.

This ensures that drivers can maintain their focus on the road ahead, reducing the chances of accidents caused by distracted driving.

The Cost of Replacing or Repairing Auto-Dimming Mirrors

Auto-dimming mirrors are sophisticated technological devices that add value to the driving experience. However, in the event of damage or malfunction, repairing or replacing these mirrors can incur additional costs.

Here are some factors to consider when assessing the cost of replacing or repairing auto-dimming mirrors:

1. Mirror Type:

The cost of replacing or repairing auto-dimming mirrors can vary depending on the type of mirror and its complexity.

Side mirrors tend to be more expensive due to their additional functionalities, such as integrated turn signals or blind spot indicators. Rearview mirrors, on the other hand, may be less costly to replace or repair.

2. Manufacturer:

The cost of auto-dimming mirror replacement or repair can also depend on the vehicle manufacturer.

Different manufacturers may have different pricing structures for their replacement parts or repair services, so it is advisable to check with authorized dealerships or service centers to obtain accurate cost estimates. 3.

Warranty Coverage:

Many vehicles come with a warranty that covers various components, including auto-dimming mirrors. It is essential to review the terms and conditions of the warranty to determine if the replacement or repair costs can be covered under the warranty’s provisions.

Warranty coverage can significantly minimize or eliminate the cost incurred by the vehicle owner. 4.

Technician Labor Charges:

The cost of replacing or repairing auto-dimming mirrors may also include technician labor charges. The labor costs can vary depending on the complexity of the repair or replacement process and the hourly rates of the technicians performing the work.

It is advisable to obtain multiple quotes from reputable service providers to ensure a fair and reasonable price. 5.

Additional Functionalities:

If the auto-dimming mirror includes additional functionalities such as integrated cameras, compasses, or temperature displays, the cost of replacement or repair may be higher to account for these additional features. 6.

Insurance Coverage:

Some insurance policies may provide coverage for the replacement or repair of auto-dimming mirrors. Review your insurance policy to determine if this coverage is included or if it can be added as a supplemental coverage option.


Auto-dimming mirrors have a significant impact on night-time driving, improving visibility, reducing glare, and enhancing overall safety. By reducing glare, enhancing contrast, and minimizing eye strain, these mirrors promote a more comfortable and focused driving experience.

However, in the event of damage or malfunction, the cost of replacing or repairing auto-dimming mirrors can vary depending on factors such as mirror type, manufacturer, warranty coverage, technician labor charges, and additional functionalities. It is essential for vehicle owners to consider these factors and explore their options to make informed decisions regarding the repair or replacement of auto-dimming mirrors.

How to Upgrade from Standard Mirrors to Auto-Dimming Mirrors

Standard mirrors, while simple and affordable, lack the advanced features and benefits of auto-dimming mirrors. If you want to upgrade your vehicle from standard mirrors to auto-dimming mirrors, there are several steps you can take to make this enhancement.

Here’s a guide on how to upgrade from standard mirrors

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