... /NAAMM-MBG531, BS4592, AS1657, JS31011.3 Grating Dimension Load Bearing Flat Bar sizeThickness≥3mm, depth ≥19mm19X3,19X5,20X3, 20X5, 25X3, 25X4 ... .5, 25X4.7, 25X5…..40X6, 40X8, 40X10,….90X6….Pitch of Load bearding flat bars(mm)12.5,15, 20, 30, 30.6 ... cross bar2. Types of Drainage/Ditch Cover: a. Normal type; b. U type; c. Security type (anti-theft)2.1 Normal type of Drainage/Ditch Cover ...