UEi Test Instruments EM201 Differential Digital Manometer Dual input differential measurement to 40-Inch WG or 100mBAR Triple Scale: inWG, mBar,-and PSI Protective rubber boot with built-in agnet for hands-free operation Min/Max value capture and data hold Includes: Brass fitting valve adapter and ressure tubing Dynamic Min/Max value capture Data hold Backlit display Ruggedized, including rubber boot with integral magnet Auto power off Test gas and static pressure on HVAC systems Test pressure switches Pressure tubes w/ brass fittings 2 (BF100) Battery (9V) Manual (EM151/201B-MAN)