Dwyer Instruments, Inc. Series ADPS Adjustable Differential Pressure Switch is designed for pressure, vacuum, and differential pressures. The scaled adjustment knob allows changes to the switching pressure to be made without a pressure gage. Available with settings from 0.08? W.C. (20 Pa) up to 16? W.C. (4000 Pa). T It can be used in monitoring air filters, ventilators, and industrial cooling-air circuits along with controlling air and fire-protection flaps and many other applications.