Cotterman® welded aluminum rolling ladder is up to 50% lighter than comparable steel ladders. Aluminum is clean and corrosion-resistant. 350-lb. load rating. 7"D steps, 14"D top step, and handrail. Serrated, open grip tread allows liquids to drain quickly. For oily, wet, or outdoor environments. Provides maximum slip resistance in most environments. Spring-loaded casters help lift ladder off its legs when stepping off. Meet OSHA and ANSI standards.Note: A Cal/OSHA compliant unit may be substituted for ship to addresses into the State of California.