Measure both pressure and air velocity Read the red figures directly in feet per minute of velocity - from 400 to 10,000 fpm No conversion tables needed for air at standard conditions. Read the black figures in inches of water column air pressure - from 0 to 10" w.c. Our most popular precision air velocity instrument, the No. 400 is used to balance air conditioning systems, measure pressure drop across filters, and test fan and blower discharge and inlet pressures, as well as air velocity in ducts. It offers the convenience of a dual purpose instrument - plus high accuracy on easy-to-read scales. The Series 400 includes "leveling" adjustment and glass bubble level, which makes it a versatile, all around manometer for the air conditioning and balancing contractor or industrial plant. Kit includes No. 400 Air Meter and all accessories: Combination Inclined/Vertical Manometer. Dwyer® Durablock precision machined solid acrylic plastic construction is virtually indestructible. Has both inclined section for high accuracy and vertical section for extended range. Pressure marked in black, Velocity in red figures. Easy to read - no reference tables needed. Has screw leveling adjustment and ground glass bubble level.
