... 310 321 Standard:ASTM A213 A269 A312 A789 B163 B407 comBefore paying, please agree with the supplier ... ASTMCertificationISOWelding Line TypeERWThickness0.3-25mmshapesquareGradeASTM A213, A269, A312, A789, B163, B407Payment & Shipping Terms:Price:FOB USD 1000~2400 / ... Descriptionstainless square steel pipeStandards:ASTM A213, A269, A312,A789, B163, B407Steel grade: TP 321, 310, 904, duplexrectangular ...