Pneumatic Electric Switch, 2-24 PSI Setpoint Range, 2 PSI Differential Pressure Range, Surface Mount, Barb Fitting Air Connection for 1/4" OD Plastic Tubing, 40-140 Degree Temperature Range, 5-95% RH Operating Humidity Range, Make R-W on Pressure Riseto Setpoint plus Differential, Make R-B on pressure Fall to Setpoint, Switch Operation Converts Pneumatic Signal to Electrical Switching Action (SPDT)