... strength, (2)light structure, (3)good appearance (4)durable in use HDG steel grid/steel grating for ... , BS4592, AS1657, JS31011.3 Grating Dimension Load Bearing Flat Bar sizeThickness≥3mm, depth ≥19mm19X3,19X5,20X3, 20X5, ... 25X5…..40X6, 40X8, 40X10,….90X6….Pitch of Load bearding flat bars(mm)12.5,15, 20, 30, 30 ... and dimension is not limited to above.1.4 Grating type: flat bar: plain type, plain I type, ...