Model "D" SALES A KIT FOR PRODUCT CODE: 2B4-3B27-12400000D; Pressure Reducing Regulator, Tfe Gaskets; 1/2" Size; Bronze Body & Spring Chamber; B2 Trim: Brass With Buna-N (Nbr) Seat,Neoprene (Bc) Diaphragm;Opt-4: Stabilizer (Recommended For Gaseous Service Only)