Features: The instrument is equipped with a TPU sheath with a simple hose connection device. Power supplied by 1 pc 9V 6F22 battery.  Measuring negative/positive/differential pressure, with the following optional units of measurement: bar, ozin², psi, inHg, mbar, mmHg, cmH2O, ftH2O, inH2O, Kgcm² and Kpa, a total of 11 common units.  It is suitable for detecting waste gas negative pressure, the engine intake manifold vacuum negative pressure, ventilation duct system pressure measurement, and line pressure stress tests in the troubleshooting of the system. Manual and auto power off to meet the demand of users of different field measurements. The instrument is simple and easy to use with clear reading value, suitable for the automobile repairing industry and HVAC industry. Specifications: Item Name: Digital Pressure Manometer Main Material:  Plastic Measuring Pressure Type: Positive/Negative/Differential pressure Measurement Range: ±30Psi/206.8Kpa Pressure Unit: bar, ozin², psi, inHg, mbar, mmHg, cmH2O, ftH2O, inH2O, Kgcm², Kpa Accuracy: ±1%FS Repetitive: ±0.25%FS Response Time: ≈0.5秒（25℃±2℃） Pressure Connection: 1pcs 1/8”( 3.18mm ) quick coupling Multi-function: MAX/MIN/AVG/DIF Data Is Stored: 32 Set Power: 9V 6F22 Batteries*1PCS Auto Power Off: Auto Power Off/ Manual Shutdown Color: Blue Size: 155*80*32mm Package Information:  Package Size: 24*21*5.5cm Package Weight: 550g Package List: 1 * Pressure Meter 1 * Hose 1 * 9V 6F22 Battery 1 * Rubber Head 1 * Metal Quick Connector 1 * PP Tool Box Packing 1 * Product Manual