... gratings complying with many international standards, such as the China YB/T4001-1998, America ANSI/NAAMN (MBG531-93), England (BS4592-1 ... StylePlain / Smooth, Serrated /teeth, I bar, serrated I bar 7StandardChina: YB/T 4001.1-2007, USA: ANSI/NAAMM(MBG531-88),UK ...