Features: - Digital display with blue LED - Used to measure the oil pressure of automobile - Measurement range is -14 psi to 40 psi - Used to measure the pressure of vacuum pressure - High accuracy and easy operation Specifications:  - Item Name: Boost Gauge - Boost Gauge: -14 to 40PSI - N.W.: 0.15kg Installation Instruction: - Connect Part 1 to Part 2. And powered by 12V. - There are two buttons in Part 1. - Press buttons and LED will flash. - Press these two buttons to set alarm number. - Press left button down & right button up.