Material:Mild steel.. Size:Standard,OEM High quality Grating stair treads ISO 9001:2000& 20 years' supplier YB/T4001.1-2007. steel bar grating:1.) Processing technic:Steel grating is made by bearing bar and cross bar according to the flat-steel weft arrangement, in high-pressure spacing on resistance welder welded by cutting, incision, opening, overlock process such as processing and into ...