... :API,ISO,CE,eg astm a105n carbon steel weld neck flange size 1/2" to 24" ASME B16.5 24"to ... , SWF, BL, OF,LF,PLFaceRF, FF, MF, MFM, RJ, TG, RTJ, SRF,PressureClass 150Lbs, 300Lbs, 600Lbs, 900Lbs, 1500Lbs, 2500Lbs,Etc /PN6 ... , etcSpecial design available as the requirement of customer Slip On Flange Blind FlangeWelding Neck Flange ISO certificate blind flange(supplier)