Specifications: 1. Wireless CPU to display communications, there are not any wire between the main board and the display. 2. Digital LED showing obstacle distance 3. Alarm by Bi-Bi sound 4. LED display with three colors (Red, yellow & green) 5. Crescent shape digital display screen 6. Turn on/off the voice according to your desire 7. All kinds of sensor colors and styles are available 8. High quality and easy to install Technia: 1. Rated Voltage: 12V DC 2. Operating Range: 10.5V～ 16V DC 3. Rated Current: 50mA～ 180mA 4. Detecting Distance: 0.3～ 2.0m 5. Ultrasonic Frequency: 40KHz 6. HF Frequency: 315MHz / 433MHz 7. Display Working Temperature: -30 ～ +70℃7.