... pipefittings collection in th emost standard and material. FLANGE: WELDING NECK ,SLIP ON ,BLIND ,PLATE,THREADED,LAPPED ,SCREWDE,SOCKET ... PACKAGE Remark: 1)GOST 12820:PLATE FLANGE GOST 12821 :WELDING NECK FLANGE2)JIS 2220:SOP:PLATE SOH :SLIP ON BLIND3 ... 4504:SLIP ON ,WELDING NECK ,PLATE,BLIND,THREADED6) SABS1123:SLIP ON ,WELDING NECK ,PLATE,BLIND Carbon Steel Forged gost12821 pn 6 welding neck flange