The HD755 Differential Pressure Manometer, with 11 configurable units of measurement, can function as a short-range/high-resolution Gauge or offer Differential Pressure ranging from 0 to 13.85 in. H2O. The Max/Min recording and Relative time stamp functionalities, as well as the HD755’s Data Hold and Auto Power Off modes, are useful. to buy EXTECH HD 755 visit our website.