MagiDeal 3in1 Oil Temp Water Temp Oil Pressure Gauge Sensor for Auto Car Truck Meter Voltage: DC 12V Diameter:2. Fits for Most of 12V cars/trucks/tractors and marine engines Oil pressure gauge indicates: Low Oil Level; Clogged oil filter;Loose or broken oil line;Oil foaming;Improper oil viscosity;Engine bearing failure Water tempereture gauge indicates: Low coolant level;Defective thermostat;Broken fan belts;Blocked radiator;Leaking cooling system