HOTSYSTEM Electronic Universal Water Temp Temperature Celsius Meter Gauge Blue Digital LED DC12V 2inches 52mm for Car Vehicle Automotive The measurement unit of this gauge is Celsius, we also have Fahrenheit gauge! Read range:Our gauge will precisely monitor the temp within your coolant that is within a range of 40 to 150 Celsius. The warn light will light up when temp is higher 100. Easily display at night:Our gauge is highly visible with a blue digital LED,easy viewing at all angles during any lighting conditions. Easy installation:Our gauge includes electric wire,temp sensor with necessary mounting and installation hardware. Note:Please make sure the voltage is DC12V,and this gauge is only used to measure water temperature! This gauge will precisely monitor the temp within your coolant that is within a range of 40 to 150. This  series is fully electronic with a blue digital LED readout, which  allows for easy viewing at all angles during all lighting conditions. Each gauge includes an temperature sensor with all necessary mounting and installation hardware. Also included is a feature allowing your gauge to dim for night driving when your headlights have been switched on. When  powering up your Blue Digital gauge, the user will be alerted to a  startup sequence to ensure your gauge is functioning properly and that  it is calibrated correctly.