The professional car parking sensor consists of ultrasonic sensors， digital control box， and LCD display.New LCD parking sensor is with 4pcs rear black sensors!easy to connect from display to main unit，no wire connection.Product Features:Numeral and color LCD display        Step up buzzer alarm                         Left and right obstacle indication         Numeral display from 1.8m to 0.3m                                                                             Display unit with built-in buzzerBuzzer alarm switch:on/off          4 black ultrasonic sensorssensor diameter:22mDisplay size: 96*27*20mmCar Parking Sensor Specification:Rated voltage:DC12VOperating range:DC9V-18VRated current:20mA-200mADisplay distance:0.3-1.8mUltrasonic frequency:40khzworking temperature:-30 degrees to +80 degreesFrequency:433.92mhzPackage includes:1x Car parking sensor4x Rear black sensor1x Power cable1x Manual