Features 1、Wide range of application, suitable for ships, yachts, trucks, commercial vehicles, construction machinery. 2、Stainless steel material, water resisting, sturdy, has long service life, not easy to damage. 3、Can freely switch the speed unit of kont, mph, km/h, which is convenient for you to watch and provides you with more convenience. 4、The navigation pointer supports 8 direction pointers, bringing you more convenience. 5、Small, light and easy to install, no other complicated steps are allowed, bringing you more convenience. Specifications: Item Type: Speedometer Material: 316 Stainless Steel + ABS + PC Input Parameters GPS Signal Working Voltage: 9-30VDC Working Current: <100mA Working Temperature: -20-70℃ Storage Temperature: -30-80℃ Proof Rating: IP67 Wiring Connection: 1. Black Line: Negative Power Supply (-) 2. Red Wire: 9-30VDC Display Function: SOG: Ground Speed TRIP: Single Mileage, Cleared when Power Off ODO: Accumulated Mileage, Saved when Power Off COG: Heading, Clockwise Angle of True North Battery Voltage: 9-30V (Not Inclouded) Navigation Pointer: 8 Directions Can freely switch Kont, mph, km/h speed Units. Dial Diameter: Approx. 9.6cm/ 3.8in Installation Diameter: Approx. 8.5cm/3.3in Package List 1 x Speedometer 1 x Instruction 1 x GPS Antenna