"Cotterman rolling ladder features large casters and Safe-Lock security. Steps and platforms are made of slip-resistant, expanded metal. Durable gray enamel finish. Constructed with 1in. O.D. steel tubing to meet or exceed all OSHA and ANSI standards. U.S.A. This unit includes CAL OSHA rail kit required for California orders. Caster Size in. 4, Step Type Expanded metal, Capacity lbs. 450, Step Depth in. 7, Caster Type Safe lock, Dimensions W x D x H in. 30 x 40 x 80, Base Size W x D in. 30 x 40, OSHA Approved Yes California, Steps qty. 5, Top Step Height in. 50, Rail Height in. 30, Top Width in. 26, Material Type 1 in. O.D. steel tubing, Finish Type Gray. Built-in CAL OSHA rail kit"