Features: 1.3 Units: Three units can be switched, km/h, miles/hour, knot (rounded to one decimals). GPS SOG: 0?600km/h range; ODO: 0?999999km range; Travel: 0?999.9km range; COG: Ground course (orientation pointer). 2.Characteristic: Made of 316L stainless steel, speedometer can be used for a long time even in acid and humid environments. IP67 waterproof and dustproof grade, with curved glass (with antifog function). 3.Application: GPS speed meter is suitable for cars, tractors, trucks, boats, ships, motorcycles, etc. It can also be used for engine generator sets, construction machinery, agricultural machinery, etc. 4.Firmly Installed: There is a snap together with the harness connector, for best and firmly connected, the speed odometer could work even in strong viberation. 5.Diameter: Easy to install, open an 85mm (3 3/8in) diameter and 56mm (2 3/16in) deep hole, put the gauge in it, after connecting, it takes about 30 seconds to get signal in the first time. Specification: Item Type: GPS Speedometer_x000D_ Material: 316 stainless steel + ABS + PC_x000D_ Display Range:_x000D_ GPS SOG: Speed Over Ground: 0-600km/h_x000D_ ODO: Odometer: 0-999999km (Can be adjusted by the back button.)_x000D_ TRIP: 0-999.9km (Return Zero When off electricity.)_x000D_ COG: Course Over Ground (Orientation Pointer)_x000D_ Working Voltage: 9-32VDC_x000D_ Three Units Can Be Switched: Knot; Mph; Km/H_x000D_ Protection Class: IP67_x000D_ Backlight: TFT Screen_x000D_ Input Parameter: GPS Signal_x000D_ Applicable Models: Universal for DC12V 24V vehicles, motor yachts, ships, RVs and other vehicle modifications_x000D_ Installation Steps:_x000D_ Step 1: Open a 85mm / 3 3/8in diameter round hole in your central control or other pre installation location_x000D_ Step 2: Put the meter into the opened round hole_x000D_ Step 3: Match the screw holes of the bracket to the screws on the back of the meter, then tighten the screws, and clamp the panel with the bracket and the bezel_x000D_ Step 4: Insert the power wiring harness directly into the back wiring port of the instrument, and then connect the corresponding sensor and wiring harness according to the distribution instructions, and then connect to the power supply.