The HD750 Differential Pressure Manometer has 11 configurable units of measurement and can measure differential pressure up to 0 to 138.3 inches or function as a low range/high resolution gauge. H2O (water in inches). The HD750's Data Hold and Auto Power Off capabilities, as well as Max/Min recording and Relative Time Stamp, are helpful. Additionally, the 5psi HD750 has an integrated USB interface and Zero function for offset correction or measurement. includes a durable carrying case, software with a USB cable, an AC adapter, a connection hose, a built-in stand, and a 9V battery.