4", Steel, Standard Ladder, Mini Fortress Mobile Work Stand, 500 LB Duty Rating, 500 LB Load Capacity, Center Locking Hinge, Two-Wat Casters, 17" x 43" Work Surface, 2 Planks Per Unit, Exclusive Steel Wrap Connection, Adjustable Plank Heights of 12", 24", 36" & 48", Also Use As A Workbench.