U301 Car Electromagnetic Induction Reversing Radar Parking Sensor 1. Improves parking safety. Detection in all directions without dead angle. 2. Minimize bumper damage. Totally built-in installation without impair overall appearance. 3. Indicates object distance with different beeping frequencies. The sensor antenna activates 3 types of acoustic. 4. signals during approaching an obstacle at different distances. A continuous sound of Beep approximately between 0-0.3m A short interval sound of Beep approximately between 0.3-0.5m A long interval sound of Beep approximately between 0.5-0.7m 5. Simple and concealed installation. The sensor antenna is entirely installed inside the bumper without any drilling work. 6. Maintenance free, no cleaning or washing is required. 7. Fit for any car, truck, RV or mini-van. 8. Wires to Reverse Lamp (12 Volts DC) 9. High output Piezo buzzer alert you with a beeping sound. 10.Detects object at 3 feet or less.