Features: The radars transmits signals to the lights, there are two states, 1 is for always on, 2 is flashing. Level 1 alarm: the reminder light is for always on.Level 2 alarm: the warning light flashes+the buzzer sounds. Normal state of equipment:1) After the equipment is powered on, the left and right indicator lights flash 3 times respectively.2) When the car speed exceeds 15km/h and there is a target car in the blind area, the indicator light is on, and the steering buzzer sounds and the indicator light flashes. There is blind zone at the rear of the vehicle which is easy to endanger driving safety! This system is a vehicle assistance device that helps driver lane changing safely during driving. Easy to install. Specifications: Material:Plastic Type:5V,12V Note: It needs to be equipped with a for radar warning system to use it, and cannot be used alone. Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 2x Car Blind Spot Detection