Measuring range: 2 ~ 150 PSI Accuracy: 1 PSI Operating temperature: 0 ~ 50 C (30 ~ 122 F) Easy to use: When the tire indicator on / off button is pressed, it will reset automatically and 0.0 is displayed. Press the power switch for 3 seconds to turn off the device. Measurement unit: the manometer has four air pressure measurement modes: PSI, BAR, KPa, KG / CM2. Press the on / off button several times to change the units. Multifunction: air display, LED flashlight, belt cutter, glass hammer, mode change, LED lighting. Power supply: 2 AAA batteries (not included). Product Instructions for use: 1. Measurement of tire pressure in unused condition. 2. Switch on the device by pressing the ON button. The LCD screen displays 0.0. 3. Route the air valve to the tire air valve and depress it. Make sure there is no air leakage. Hold the position until the LCD value is stable. 4. The measured value remains held for 90 seconds and disappears automatically. 5. Press ON for 3 seconds to turn off. The kg / cm are modified 6.4 kinds of pressure units: psi, bar and kpa, kg / CM2, which can press the ON button. 7. Slide the switch to turn on the LED light and flashlight.