... 30.3, 32.5, 34.3, 35, 38.1, 40, 41.25, 60, 80mm etcUS standard: 19-w-4, ... GradeASTM A36, A1011, A569, Q235, S275JR, SS304, Mild steel & Low carbon steel, etc5Surface TreatmentBlack, self colour, hot dip galvanized, painted, spray ... 1985, Japan:JIS steel grating standard picture steel grating standard workshop picture steel grating standard loading into container steel grating standard factory door ...