The ET180 Digital Differential Manometer from Klein Tools measures air and gas pressure for port 1, port 2, and measures the differential between the ports. Easily toggle between units: inH2O, bar, oz/in2, psi, mbar, kPa, inHg, mmHg, kg/cm2, ftH20, and cmH2O. Large, backlit LCD shows minimum, maximum and average values. Magnet on back for hands-free operation. Features Digital Manometer measures air and gas pressure for ports P1, P2, and differential Range of +/- 60 inH2O and full scale accuracy of +/-1.5-Percent Strong magnet on back for hands-free operation Units measured: inH2O, bar, oz/in2, psi, mbar, kPa, inHg, mmHg, kg/cm2, ftH20, and cmH2O Calculates minimum, maximum and average values Large LCD is backlit for easy viewing in low light conditions Auto-power off feature conserves battery life Hold button locks current reading on the display Silicon tubing, 3 x AAA batteries, and storage pouch included Includes 6.56' (2 m) x 1/8'' (3 mm) Inside Diameter Silicon Tubing, 3 x AAA Batteries, Pouch, Instruction Manual Specifications Type: Differential Pressure Application: Measure Static and Differential Pressure Special Features: Magnet on Back of Housing Modes: P1, P2, Differential Pressure Measurement Range: +/- 60 inH2O Maximum Pressure (psi): 2.16 PSI Maximum Pressure Reading (wc): 60.0 Minimum Pressure Reading (wc): -60.0 Accuracy: +/-1.5% Full Scale Measurement Units: bar, oz/in2, psi, mbar, kPa, inHg, mmHg, kg/cm2, inH2O, ftH20, and cmH2O Number of Ports: 2 Connector Type: Tapered Stainless Steel Ports from 1/8'' to 5/15'' Temperature Range: 32° to 122° F (0° to 50° C) Display: Backlit LCD Batteries: 3 x AAA Low Battery Indicator: Yes Auto-Power Off: Yes Material: ABS, Stainless Steel Overall Length: 2.47'' (6.3 cm) Overall Height: 6.19'' (15.7 cm) Overall Width: 1.38'' (3.5 cm) Standard: Conforms to EN 61326-1:2013; EN61326-2-3:2013; CE and UKCA Certified Weight: 7.2 oz (202 g)