... , non-sagging,non-dirt, and easy to install 4) Hot galvanizing standard: China GB/T13912-925) Wrapping: wrapping is ... A1011, A569, Q235, S275JR, SS304, Mild steel & Low carbon steel, etc5Surface TreatmentBlack, self colour, hot dip galvanized, painted, spray coating 6Grating StylePlain / Smooth, ... , Australia: AS1657-1985,Germany: DIN24537-1-2006, Japan:JIS galvanized steel grating ladder (factory)