Fangrui Product Details 1. Car Parking Reversing Buzzer & Led Sensors 4 Safe Sensor 2. Features 3. Working Voltage: Dc 9~15v 4. Working Current: 40ma~200ma 5. Max Power: 4w(max) 6. Farthest Distance: 2.0m 7. Siren Sounds Distance: 0.3~2.0m 8. Siren Volume: 85~105db 9. Working Temperature: -40~80c 10. Operations 11. Start Up Reversing System, Reversing Lights Flash And Buzzer Sounds "bi", Then Parking Sensor Turns On Automatically. 12. When Vehicle Reverse Away 2 Meters From Obstacle, Digital Lcd Shows Obstacle Place And Distance. 13. Install Lcd: Fix Lcd With 3m Double Glue Sticker On A Suitable Place Of Driving Room 14. Install Control Box: Fix Control Box With 3m Double Glue Sticker In A Suitable Place In Truck 15. Wire Connection: Lead The Wire Into Vehicle Truck Suitable Place Through Holes On Vehicle And Bundle Wire, Then Connect Detector, Control Box And Color Digital Lcd Described As Illustration. Finally Connect The Positive And Negative Power Wire With The According Color Power Wire On Reversing Light 16. Test And Adjust: After Installation Completion, To Test According To "operation". Free To Choose The Probe Quantity, But Shall Connect Probe According To Label Requirement.