... high strength 3.material saving:slip-resistant&safe hot sale steel grating combined 1) Bearing bar specification:20*3 ... A569, Q235, S275JR, SS304, Mild steel & Low carbon steel, etc5Surface TreatmentBlack, self colour, hot dip galvanized, painted, spray coating ... 6Grating StylePlain / Smooth, Serrated /teeth, I bar, serrated I bar hot sale steel grating ...