... should be untreated,painted or hot dipped Galvanzied Specification:steel grating No.ItemDescription1Bearing Bar25x3, 25x4, 25x4.5, 25x5, 30x3, ... , 32x5, 40x5, 50x5, 65x5, 75x6, 75x10---100x10mm etc; I bar: 25x5x3, 30x5x3, 32x5x3, 40x5x3 etcUS standard: 1''x3/16 ... , spray coating 6Grating StylePlain / Smooth, Serrated /teeth, I bar, serrated I bar 7StandardUSA: ANSI/NAAMM(MBG531-88),UK: BS4592-1987 ...