SMA Products TEEJET POLY PRESSURE RELIEF VALVE - 1/2" - 878-2312012PP Features: 23120 Series Poly Pressure Relief Valve Bypasses excess liquid. Adjustable to maintain control of line pressure at any pressure within the valve's operating range. Selected pressure setting firmly held in place by locknut. 302 stainless steel spring and EPDM O-ring. Excellent chemical resistance. 1/4" port for pressure gauge - pipe plug included. TechSpecs: Brand: TeeJet Interchanges: 5143200231201/2PP 5143200 231201/2PP This is an aftermarket part.