Standard:ASTM,API,JIS,BS,GB Grade:10#,20#,ST35,ST37,ST52,16Mn,A53-A369,API J55-API P110,Cr-Mo ... alloy OD:21-610mm T:2-60mm ASTM A53/A106 steel pipe/tube Brand: zhcxStandard:ASTM,API,JIS,BS,GBGrade:10#,20#,ST35, ... ST37,ST52,16Mn,A53-A369,API J55-API P110 ... quote you the best prices with good quality. ASTM A53/A106 steel pipe/tube