Electrically Activated Hydraulic Cylinders Are Built Into Each (4) Corner Steel Leg. Motorized Lift System Can Securely Lift 1100 Lbs From 20 Wheelchair Height To 30 High. Static Load Tested To 4400 Lbs. Seamless Nylon Reinforced Vinyl Is Tear Resistant.plywood Reinforced Subtop For Added Strength.extremely Stable Lift System Elevates From 20 Wheelchairheight To 30 High.hands-free? Foot Control. Seamless Nylon-reinforced Vinyl Is Wear And Tear Resistant. 2 High-density Urethane Foam Vinyl Top. Steel Frame And 4 Corner Legs Have Durable Black Powder Coat Finish. Legs Have Levelers For Uneven Floors. 4-leg Open Design Is Patient Sling-lift Accessible On Al Four Sides Hospital Grade Plug. Upholstery: Choice Of (4) Nylon-reinforced Vinyl Colors You Must Specify Upholstery Color With Order.