The meter can measure the differential pressure conveniently. It features 11 selectable units of measure: inH2O， psi， bar， mbar， Kpa， InHg， mmHg， ozin2， FtH2O， cmH2O， kgcm2. It's used for testing ventilation and air conditioning system， spot check， clean room， or any gas pressure system troubleshooting. Features:Large LCD backlight display， providing clear reading.11 selectable units for measurement， convenient for use.Max./Min./Avg values， and with a relative time clock.Low battery indicator and pressure unit indicator.Zero adjustment， offset and DIF function.Data hold and automatically shutdown function.Specifications:Display: LCD BacklightInH2O Range: ±55.40; Resolution: 0.01Psi Range: ±2.000; Resolution: 0.001Mbar Range: ±137.8; Resolution: 0.1Kpa Range: ±13.79; Resolution: 0.01InHg Range: ±4.07; Resolution: 0.001MmHg Range: ±103.4; Resolution: 0.1Ozin2 Range: ±32; Resolution: 0.01FtH2O Range: ±4.612; Resolution: 0.001CmH2O Range: ±140.6; Resolution: 0.1Kgcm2 Range: ±0.140; Resolution: 0.001Bar Range: ±0.137; Resolution: 0.001Accuracy: ±0.3%FSO(25°C)Repeatability: ±0.2%(Max. +/-0.5%FSO)Linearity/Hysteresis: ±0.29%FSOMax. Pressure: 10Psi Response Time: 0.5s Typical Low Battery Indicator: YesOver Range Indicator: Err. 1Under Range Indicator: Err. 2Operating Condition: 0-50°C / 32-122°FStorage Condition: -10-60°C / 14-140°FPower Supply: 1 * 9V Battery (NOT Included)Item Size: 170 * 55 * 33mm / 6.7 * 2.16 * 1.3inItem Weight: 127g / 4.51ozPackage Size: 25.5 * 14 * 6.5cm / 10 * 5.5 * 2.56inPackage Weight: 229g / 8.07ozPackage List:1 * Digital Manometer1 * Leather Pouch2 * Flexible Tube1 * Metal Accessory1 * User Manual (English)