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 ... 25 x 5 x 3, 32 x 5 x 3, 38 x 5 x 3, 40 x 5 x 3, 50 x 5 x 3 ... ) Bearing Bar Pitch (center to center): 12.5, 15,25, 30, 30.16, 32.5, 34, 40, 41.25, 45, 50, 60 ...