... :API,ISO,CE,eg astm a105n carbon steel weld neck flange size 1/2" to 24" ASME B16.5 24"to ... ,PressureClass 150Lbs, 300Lbs, 600Lbs, 900Lbs, 1500Lbs, 2500Lbs,Etc /PN6,PN10,PN16,PN20,PN25,PN40/ Class A, B, C, D, EstandardASME B16 ... , etcSpecial design available as the requirement of customer Slip On Flange Blind FlangeWelding Neck Flange ISO certificate DIN standard ...