The Dwyer 477B manometer is hand-held and battery operated for easy use. This digital manometer is designed for use with air and compatible gases in applications like lab calibration of other pressure instruments or air velocity and air flow measurements in commercial buildings. It has a backlight feature to help in dark and low light conditions.

The connections depend on the model that you select. Two barbed connections for use with 1/8 inch (3.18mm) or 3/16 inch (4.76mm) I.D. tubing come with models 477B-1, 477B-2, 477B-3, 477B-4, and 477B-5 only. On the 477B-6 and 477B-7 you'll get two compression fittings for use with 1/8 inch (3.18mm) I.D. x 1/4 inch (6.35mm) O.D. tubing.

This unit comes with a low battery indicator because a weak battery can cause improper operation or inaccurate measurements. There is also potential inaccuracy due to temperature effects but that can be minimized by using the zeroing feature before use.