... :ASME B16.5 5.Certificate:API,ISO,CE,eg astm a105n carbon steel weld neck flange size 1/2" to 24" ASME B16.5 24"to 80" ASME B16 ... ,PN25,PN40/ Class A, B, C, D, EstandardASME B16.5, ASME B16.47, ASME B16.36,DIN2505,EtcMaterialCarbon steel(ASTM A105,Q235,A350LF2,A350LF3,Etc ... design available as the requirement of customer Slip On Flange Blind FlangeWelding Neck Flange ISO certificate ansi standard ...