... .ASTM A123,SS400 3.Common pitch:30mm&40mm 4.Used in flooring,walkway Steel Grating Stairs Steel ... ,34.33mm,35.33mm,38mm,40mm,41.25mm,50mm,60mm4. Steel Grating Stairs Cross Bar Pitches: 38 ... .1mm, 50mm, 75mm, and 100mm,101.6mm(4") etc.5. Steel Grating Stairs Standard ... thickness of bearing bars 3.Surface:serrated or smooth 4.Dimensions of area 5.Span(direction of bearing bars) ...