4 sensor system, double CPU and advanced chipset for enhanced coverage and detection (0-2.5m). With digital colored LED display (number; light). Help to prevent dangerous and costly collisions. Help to provide increased safety for passengers, pedestrians and family members who happen to be around the moving vehicle. Detect small children and low walls as well. Anti-freeze and rain proof. Easy to install. A saw drill head included. Specifications: Rate voltage: 12V DC Rate operating range: 10.5V - 16V DC Rate current: 100mA - 300mA Detecting distance: 0.3 - 2.0m Ultrasonic frequency: 40KHz Control module working temperature: -30 - 80 celsius degree Display working temperature: -20 - 70 celsius degree LED display size: 9 * 1.5cm.