Pressure/Vacuum Generator For Use With Manometer Multimeter Function Calibrate or Test HVAC Air Flow Sensing Switches Set Points +/-0.1 to +/-12.0 in wc 1/8 and 1/4 Adapter Thread Fitting (F)NPT Features Handheld Constant Air Source Fine Tune Output Adjustment Potentiometer Operating Temperature 50 Degrees to 120 Degrees F Battery Type (3) AA Includes Tubing Kit Batteries Hand Held Attached Case