... I-shape 4>Hot-dipped galvanized,Painted,Untrea 1.Bar Grating Standardizations:CountriesNational Standards for GratingMaterialsGalvanizing Standards ChinaYB/T 4001.1 ... 1mm, 50mm, 75mm, and 100mm,101.6mm(4").5.Standard Grating Panels Sizes: 3'x12', 3'x20', 3'x24'.6. ... .Serrated:Better non-skid property & safety compared with plain grating.I-Shape:lighter,more economical and practical compared with plain ...