Be suitable for all kinds of tacho RPM sensors, and display the rotation speed of the engine.IP67 waterproof and .With curved glass (with anti-fogging function)With ultra-wide working voltage design( long-term operating voltage: 9-32V, Maximum up to: 36V (less than or to 1 min)).Technical Data:Indicating Range: 0-9990RPMSpeed : 1-300 adjustableWorking Voltage: 9-32V(12V/24V)Backlight: RedFunctions: current tacho/RPM and hourOperation mode: LCD display, colour:blackMaterial:ABSsize:52mmPackage Contents:1x Tachometer1x Multi-plug socket1x Installation InstructionOnly the above package content, other are not included.Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.