Open a 3-3/8 inch dimension and 2-1/5 inch depth hole, put gauge into it and fastenMade of high-quality 316 stainless steel for long-term use even in acid-base, humid environmentA 4-in-1 multi-function digital meter integrating Tachometer, Water Temp, Oil Pressure Gauge,and VoltmeterThe instrument has its own alarm signal, and no need additional alarm signal by the sensor.High brightness LED backlight, high brightness and long life.Operating Voltage :9-32V DCPower Consumption : Less than 120mAOperating Temperature :-20-70 degreesStorage Temperature :-30~80 degreesDegree of Protection :IP67Sensor Fault Alarm(Chinese and English can be switched)Setting:Keep on pressing the back button for 3 seconds, and then enter into setting mode, if leave button more than 3 seconds, it will be out of setting mode.The value will increase when you press the button. When you leave the button and then press it again, the value will decrease. The minimum step value is 0.1 and the adjustable range is 1-360.(tachometer setting)When you get the required speed ratio value after adjustment, please leave the button. The tachometers will autoclave your setup after 3 seconds. If the setup doesn't meet your demand, please re-setup.Must press the button first and power up, can select English or Chinese.Colour:blackMaterial:stainless steelSize:85mm diameter (3-3/8inch)55mm Depth (2-3/4inch)Package Contents:1 x 4 in 1 Multi-function Gauge1 x Multi-plug socket1 x Chinese and English manualOnly the above package content, other products are not included.Note: Light shooting 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.