... 4Material GradeASTM A36, A1011, A569, Q235, S275JR, SS304, Mild steel & Low carbon steel, etc5Surface TreatmentBlack, self colour, hot dip galvanized, painted, spray ... : AS1657-1985, Japan:JIS Keywords : steel grating , bar grating , welded steel grating , Trench grating , serration grating , safety flooring , industrial grating , close mesh steel grating , foot rest grating and so on 8)the ...