The Dwyer ADPS-03-1-N Adjustable Differential Pressure Switch is designed for pressure, vacuum, and differential pressures. The dual scaled adjustment knob in inches water column and pascals allows changes to the switching pressure to be made without a pressure gauge. The ADPS-03-1-N is available with settings from 0.20 in w.c. (50 Pa) up to 2.0 in w.c. (500 Pa). The silicone diaphragm and PA 6.6 body make the series ADPS ideal for use with air and other noncombustible gases. The ADPS031N meets UL508 and are constructed of plenum rated plastics. The compact size, adjustment knob and low cost make the ADPS-03-1-N the perfect choice for HVAC applications.