... smooth or serrated 3.finish:black painted,mill,galvanized hot dipped galvanized steel grating 1.Material: SS302,SS304,SS316,SS310,SS314, ... ANSI/NAAMM(MBG531-93) 4) Austrilia: AS1657-19927.Fields of Application:Platforms ,sidwalks,filter grates, ventilation grates,driling stages ... ,ditch grates,fences, framedgrates,trash rack grates8.advantage:Light weight, great load-bearing capacity, non-slip and safe, ...