... resistance welding ring which is controlled by computer, So we can produce high quality gratings ... General Specification: 20*3, 25*5, 25*3, 30*3, 32*5, 40*5, 50*5, 65*5 etc.Cross bar: Q235A ... or 304 stainless steel wire, General Specification: 5*5, ... corridor, bridge, well covers, stairs.5. Ventilation, light leakage, thermolysis, antiskid, explosion-protection. ...