Model 31-N Rev A Low Pressure Reducing Gas Regulator; 3/4" Body Size, #2 (0.125") Orifice; Sales Kit A; Carbon Steel Body, Stainless Steel Lower Case, Carbon Steel Spring Chamber, Arrangement/Position 1, Internal Sensing Unless External Sensing Option Is Specified; S40V Trim: 316L Stainless Steel Internals, Fluorocarbon Elastomer (FKM) Seat And Diaphragm,Glass Filled Nylon Load Ring