... 2.outer diameter:18-406mm 3.material:20#,45#,12Cr1MoV 10# CARBON STEEL PIPEStandard: GB,ASTM,DIN,JIS; Grade ... : 10#, 20#, 45#, 16Mn; Application: Structure Pipe,Fluid pipe, low /mid ... the production process are according to the ISO9001:2000 strictly 10# Carbon Steel Pipe