Functions/Measurements: Altimeter for altitude measurement Compass for direction indication Driving distance, Driving time, Speed, Overspeed warning, Fatigue warning after 8 hours of continuous operation, Clock, etc. Screen size: 5 inches Dimensions: 145 x 69 x 62 mm Operating voltage input: DC 5V Plug and play design - Connection via USB cable to car lighter adapter/USB port 5V (cable included). Built-in automatic brightness adjustment sensor. Adjustable arm for multiple mounting options. Dashboard mounting with double-sided adhesive base. Automatic on/off with vehicle battery on/off.