This boost gauge is easy to install, but we strongly recommend professional installation. This unit is designed for most DC 12V vehicles to upgrade their measurement to be accurate and faster. Its measurement range can reach to 30 IN.HG and 30 PSI. Features - ColorAssorted Color - Product material: ABS - Size: 11x8.7x9cm - Measurement range:30 IN.HG-30 PSI - Product voltage: 12V - Unit conversion of pressure value: 1mpa = 300in-hg = 145psi - Diameter: 52mm - Wiring installation mode: supply is positive and the black power supply is negative. - Further upgrade machine core, the pressure measurement is more accurate and faster. - Easy to install, simple wiring and non-destructive installation. - Beautiful appearance, circular polishing outer ring, colorful LCD display, pleased to eyes. - 12V general type charging table, applicable to most models. - Clear Dial display and numerical accuracy, temperature range can reach to 30 IN. Hg and 30 PSI. - Warm Tip: Dear buyer, Due to lighting effect,monitor’s brightness,manual measurement and etc, there could be some slight differences in the color and size between the photo and the actual item. sincerely hope that you can understand! Thank you! Package list: 2 Gauge