Low Cost and Precision Made. The A1 Pressure Control provides the flexibility required for industrial applications. The A1 pressure switch is ideal for panel mounting wherever a high quality economical open case control is required. Optional weatherproof housing meets NEMA 4X standards. Superior 15 A contact allows direct control of a motor or pump without the use of external relays - a true time and money savings. Unique features include broad temperature limits for increased application possibilities and convenient indicating scale for quick and easy field adjustment. The rugged A1S construction incorporates the feature most often requested by customers; a 316 SS diaphragm pressure element for exceptional compatibility and long service life.