Industrial step ladder: 1. P ,S ,I type ... welding or bolts 4. width:125-305mm Industrial step ladder: We manufacture different styles of stair ladders that ... black and hot dip Galvanizing / and stainless gratingUsage: ladder, flooring walkway, platform ,steel structures, stair tread, ... gratings, storage shelves,fences and handrail so on for construction project, oil project, seaport, power plant, ...