Features: Theparking system automatically recognizes and displays the distance tothe nearest obstacle, and the sensitivity of the sensor can be adjustedto prevent false alarms 4 sensor system Double CPU and advanced chipset for enhanced coverage and detection (0-2.5m). Help to prevent dangerous and costly collisions. Helpto provide increased safety for passengers, pedestrians and familymembers who happen to be around the moving vehicle. Detect smallchildren 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 Control moudle working temperature: -30 - 80 Celcius degree Ultrasonic frequency: 40KHz Size:As picture Weight:About 358g Package included: 1 x Main Control Box 4 x Parking Sensors with 2.5M Line 1 x Buzzer Display 1 x Hole Saw 1 x Power Cable 1 x User Manual Do drop