... grates, 3. serrated steel flat gratingTypeWelded steel grating, pressure-locked, socket-welding Steel flat size20×3,25×3,25×5,30 ... ,50,80,100mmmaterialLow carbon steel, stainless steel, aluminumSurface treatmentUntreated, hot galvanized, paintedStandardsChina: YB/T 4001.1-2007USA: ANSI/NAAMM(MBG531-88 ...