ELING Waterproof Tachometer REV Counter RPM Gauge Kit With Hour Meter 0 6000 85mm12V 24V for Car Boat Van Backlight

Open a 85mm dimension and 70mm depth hole, put gauge into it and fasten Speed Ratio: 1-300 adjustable, You can press the back button to adjust it. Idle speed is typically 600-800rpm. Details refer to owner manual. Suitable for diesel engine and gasoline engine. Tachometer can get signal from engine, ignition coil, crankshaft sensor, or tacho sensor (be sold separately), etc..If you need tacho sensor, pls. search for ASIN NO. B07WPXL7WQ or B07WPXFH34 It shows rpm and hour. Hourmeter cannot be reset. Red Backlight, 9-32VDC(12VDC/24VDC) Working Voltage, 100% Waterproof and anti-fogging protection