CHECK VALVE (NON RETURN VALVE): Feature Type : Bolted Cover, Swing Type, Lift Type, Wafer Type Design Disc : Composition Disc, Metallic Disc. Size Range : 15mm To 400mm & Above On Request Pressure Rating : 150#, 300#, 400#, 600#, 800#, 900#, 1500#. End Connection : Flanged Ends, Socket Weld Ends, Screwed Ends & Butt-Weld Ends. Mfg. Std. : BS-1868, API - 6D Testing : BS - 6755-1, API-6D Material Of Construction : Cast Carbon Steel (ASTM A 216 GR. WCB, ASTM A 217 GR. WC6, WC9), Forged Steel (ASTM A 105, ASTM A 182 GR. F22, F304, F316) Cast Stainless Steel (ASTM A 351 GR. CF8, CF8M, CF3, CF3M), Alloy 20 To ASTM A 351 GR. CN7M