Product feature: - 3 color digital lcd display with buzzer built-in - "bibi" audible warning buzzer in 3 steps - detachable sensor with waterproof socket connector (optional) - digital meter distance mode, feet display available - directional indicator of left and right - 4 rear sensors for full coverage, 2 ~ 8 sensors available for front & rear detecting - all spare parts are compatible & exchangeable - different sensors & colors optional - sensor sensitivity adjusted, anti-hook memory function for tow bar and spare tire - sensor self-testing function after power on Technical specification: - rated voltage: 12v - operating voltage: 9 ~ 28v dc - rated current: 10ma ~ 150ma - detection distance: 0.3 ~ 2.5m for rear, 0.3 ~ 1.2m for front - ultrasonic frequency: 40khz - working temperature: -30oc ~ +80oc - warning: 80db -display size: 77.7*27.1*22.2mm - full-range technical support