Model "2171" Cryogenic Back Pressure Relief Regulator,Tfe Gaskets; 1/4" Size, Angle Design (Two Side Inlets - Bottom Outlet); 316l SST Body & Cf3m SST Spring Chamber, Opt-55: Cleaned For Oxygen;Service Per Spec #S-1134; S36 Trim: 316l SST With Tfe Seat,302SST Diaphragm; Npt Screwed; 70-140 PSIG SST Range Spring