... with good quality :high quality,low price,multi-standardCertificate:ISO9001:2000,CE.Size: 1/2"-48"Material: stainless steel,carbon steel ... and so on.Structure type: seamless pipe,straight steel pipe,square pipe,spiral pipe ,and so ... on.Deaign and manufacture std: DIN carbon steel flangesMaterial:Rst37.2,St37.2,C22.8)DIN2573 ... and questions. ASTM A105 Carbon Steel seamless pipe with standard size