Model "DL" Pressure Reducing Regulator For Cryogenic Service (Requires Cryogenic Lubricants During Assembly); 2" Size; Bronze Body & Spring Chamber; B5 Trim: Brass With Tfe Seat,Phos.Bronze Diaphragm; Npt Screwed; 70-150 PSIG Range Spring; Opt-25S: Stainless Steel Vented Spring Chamber Plug; Opt-56: Special Clean Per Spec #S-1542