Model "HP" Pressure Reducing Regulator, Tfe/Fkm Gaskets (Opt-45); 1/2" Size; Sales Kit B; Manganeze Bronze Body & Spring Chamber; S36 Trim: 316SST With Tfe Seat,302SST Diaphragm; 10-40 PSIG Range Spring; Opt-1+6: Differental Construction With Closing Cap; Opt-55: Cleaned For Oxygen Service Per Spec #S-1134