Package Content : Microwave sensor x2; LED light x2; LED lights connection cable x2; Main wire harness with buzzer x1; Microwave sensor connection cable x1; Silicon glue x1; 2x L Brackets, 6x Self-tapping screws(Choose the glue or this accessory (included), Cable zip ties; Bevel protractor x1; Installation manual x1. Product warranty 12 months, customer service response within 24 hours. Note! The sensor cannot penetrate metal! Please be installed by professional, read the manual carefully before installation (Sensors mounting position, height, angle and wiring guidance). Blind spot detection sensor detects the vehicle approaching alert mode: 1. When the turn signal is off, the LED will light up; 2. When the turn signal (left or right) is on, the LED (left or right) will flash and the buzzer will sound 3 times; 3. When the double flash warning light is on, the LED (left or right) will flash, and the buzzer will sound 3 times. The system host (with infineon smart chip) is integrated in two 24Ghz millimeter wave detection sensors, the detection range is 1-32.8ft (0.3-10m) , when the car approaches (objects in relative motion) your car from the side or rear and enters this blind detection zone, the LED light will flash. Car Blind spot detection system makes your driving safer by detecting vehicles approaching from the side or rear blind spots. Poor visibility in the dark, rain, or snow can also be monitored.(New version is upgraded the chip after 2023).