... bar size:20*3--100*10 3>bar pitch: various kinds We specialize in manufacturing and exporting many kinds of ... walkway,platform,stair tread,well cover,trench cover,checkered gratings, grating ladder,fencesand handrail,etc for construction project, oil project, ... Steel5) Surface Treatment:Untreated, Painting or Hot dip Galvanizing6) Steel grating standards:A) China: YB/T4001-1998B) USA: ANSI/NAAMM ...