... the window, the balcony guardrail, highway, railway guardrail etc.Steel Grating Standardizations: CountriesNational Standards for GratingMaterialsGalvanizing Standards ChinaYB/ ... 5, 30x5, 32x5, 40x5, 50x5, 65x5, 75x6, 75x10---100x10mm etc; I bar: 25x5x3, 30x5x3, 32x5x3, 40x5x3 etcUS standard: 1 ... UK: BS4592-1987, Australia: AS1657-1992, Japan:JIS Galvanized and Painted Steel Grating with standard size