Features: 11 in 1 Digital Speedometer with GPS,compass, over speed alalrm, tired driving warning, single travel distance, single travel for time, local for time display, total distance, KMH/MPH- swithcable. Overspeed alarm & fatigue driving alarm to ensure your safe in long distance driving. Large Screen & Green light display will protect eyes of driver, let driver feel more comfortable, especially for long distance driving. Speed and compass data is from satellites, timely and accurate.In particular, the direction of the compass is not affected by the magnetic field. for all for cars,trucks,bicycle and motorcycle. Specifications: Material: ABS+PC Length: approx 14.2cm/5.6in Screen size: 5.5' Power supply: USB 5V/Car Cigarette Lighter- Input voltage: DC5.0V Input current: more than 150mA Satellite positioning speed: about 1-3 minutes in open outdoor places, no satellite signal indoors (cloudy and rainy days affect satellite positioning speed) Package Includes: 1x Digital Speedometer note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item.