This product has been discontinued. Take a look at HD750 - Differential Pressure Manometer (5psi)
Extech PS106

PS106: Differential Pressure Manometer (6psi)

11 Measurement Units, High Resolution

Extech’s PS106 differential pressure manometer is ideal for field, manufacturing or lab/R&D use offering a 6psi range, readings in 11 units and high resolution. The manometer also features a large LCD display with backlighting, data hold, auto power off/disable and zero function for offset correction or measurement. This product is complete with 6 AAA batteries, two connection hoses and a hard carrying case.