Be suitable for all kinds of tacho RPM sensors, and display the rotation speed of the engine. IP67 waterproof and dustproof grade. 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 equal to 1 min)). Technical Data: Indicating Range: 0-9990RPM Speed Ratio: 1-300 adjustable Working Voltage: 9-32V(12V/24V) Backlight: Red Functions: current tacho/RPM and hour Operation mode: LCD display, stepper motor colour:black Material:ABS size:52mm Package Contents: 1x Tachometer 1x Multi-plug socket 1x Installation Instruction Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.