Product Details: Name: Car Millimeter Radar Prompt Light Blind Zone Lane Change Auxiliary Warning Light BSD Alarm Safe Driving Alarm Accessories Material: Plastic 25MM Round Light, 14MM Round Light, Blind Zone Lens Light Power Supply Voltage: 12V (V) Power: 0.2W (W) Features: Car Safe Driving Alarm Accessories refer to auxiliary equipment installed on the car to enhance the safety of the driver, prevent accidents or reduce losses when accidents occur. Installation Location: Usually installed on the A-pillar (vertical support on both sides of the windshield). Size options are 25mm and 14mm lights, depending on the configuration of the vehicle. If compatible, it can also be installed in the rearview mirror lens. Light Behavior: Level 1 Alarm: When a target is detected in the vehicle's blind spot, the light remains on (LED is on). Level 2 Alarm: The light flashes and the buzzer sounds when there is an immediate threat, such as when the driver is preparing to turn or change lanes and there is a vehicle in the blind spot. Note: The product description mentions that the warning light itself does not have a buzzer. The buzzer sound is probably part of the car's built-in BSD system (if installed). Product Includes: 1* Car Alarm Accessories Note: Please allow slight size errors (1~2cm/0.39~0.78inch) due to manual measurement, which is subject to the actual one received; Please allow slight errors in color under different monitors.