SIZE MATERIALS SEAT END-TYPE MAX. PRESSURE lrECVALWe are Operational Reliability VSGR Series Threaded Safety Valve Cast Iron safety valve, class 250, threaded inlet and outlet, forged copper-alloy disc, fully enclosed stainless steel spring AISI 302, precision lapped seats for optical flatness, and double control rings for precise opening upon overpressure and blowdown. Tested for pressure setting according to ASME Section I and leakage. Body Ductil Iron ASTM A -536 Noozle Bronze Stem Stainless Steel AISI 304 Spring Steel GENERAL SPECIFICATIONS