The HD350 is a Pitot tube anemometer and differential manometer. Measures Differential pressure in 5 selectable units of measure and includes a Pitot tube and 2 connection hoses for measuring Air Velocity/Air Flow. Additional features include data hold, auto power off, zero function, plus manually record/recall up to 99 readings. Built-in USB port. Complete with software and USB cable, 9V battery, pitot tube with two 33.5 in. (85 cm) connection hoses and hard carrying case.