The differential manometer can be used to measure air-conditioning and ventilation system or verify in the site, and clean room or any corrective maintenance of gas pressure system. It is a indispensable measuring apparatus to heating and ventilation air-conditioning for technicians, operating maintenance engineers, and scientific researchers for its simply operation and distinct reading. Features: Test the differential pressure/positive pressure/negative pressure of areas and pipes. LCD display with backlight for easy reading. Max./Min./Average value measurement function. 11 selections of measuring unit: kPa, psi, kgcm2, ozin2, bar, mbar, inHg, mmHg, inH2O, ftH2O, cmH2O. Low battery indication, calibration, zero adjustment, record model and data hold function. Compact size and light weight, easy to operate and carry. It can be used to measure air-conditioning and ventilation system or verify in the site, and clean room or any corrective maintenance of gas pressure system. It is a indispensable measuring apparatus to heating and ventilation air-conditioning for technicians, operating maintenance engineers, and scientific researchers for its simply operation and distinct reading. Specifications: Material: ABS plastic InH2O Range: 55.40, resolution: 0.01 Psi Range: 2.000, resolution: 0.001 Mbar Range: 137.8, resolution: 0.1 Kpa Range: 13.79, resolution: 0.01 InHg Range: 4.072, resolution: 0.001 MmHg Range: 103.4, resolution: 0.1 Ozin2 Range: 32.00, resolution: 0.01 FtH2O Range: 4.612, resolution: 0.001 CmH2O Range: 140.6, resolution: 0.1 Kgcm2 Range: 0.140, resolution: 0.001 Bar Range: 0.137, resolution: 0.001 Range of Measurement: 39.99kPa Accuracy: 1%FS Repeatability: 0.2%FS Linearity/Hysteresis: 0.1%FS Max. Limit of Pressure: 79.9kPa Outrange Warning: Err1 or Err2 Pressure Connection: One 1/8" (3.18mm) quick coupling Operating Temperature: 040(10%80%RH) Storage Temperature: -1060(10%70%RH) Power Supply: 3 * 1.5V AAA battery (NOT included) Item Size: Approx. 137 * 64 * 27mm / 5.40 * 2.52 * 1.07in Item Weight: Approx. 128g / 4.52oz Package Weight: Approx. 245g / 12.18oz Package Size: Approx. 23.3 * 18 * 5.5cm / 9.18 * 7.09 * 2.17in Package List: 1 * Manometer 4 * Plastic Pipes 2 * Metal Connector 1 * Storage Bag 1 * User Manual (English)