1.ISO90010:2000 2.Hot dip galvanized steel grating, bar grating, stair treads,Ditch cover , tank grating , pavement grating , Steel Grating,Bar Grating,Ditch Covert, Stair Tread,pavement gratingWe ... ) Bearing Bar Pitch (center to center): 12.5, 15,25, 30, 30.16, 32.5, 34, 40, 41.25, 45, 50, ... 3) Cross Bar Pitch (center to center): 38, 50, 76, 100, 101.6mm etc, also be according to client's requirement ...