... other large-span and heavy loading condition. Surface Treatment:Steel grating untreated: Allowing quicker delivery to customers whom ... GradeASTM A36, A1011, A569, Q235, S275JR, SS304, Mild steel & Low carbon steel, etc5Surface TreatmentBlack, self color, hot dip galvanized, painted, ... -1987, Australia: AS1657-1985,Germany: DIN24537-1-2006, Japan:JIS If you have any needs ,please contact me1.material2 ...