No assembly required. Only needs a screwdriver to mount to spa. Made from a poly-carbonate material reinforced with fiberglass. The only cover remover with a patented Easy On / Off Roller design. Requires 1/2 width of the cover behind the spa. Folds up snugly against the spa cabinet while not in use. 4 rollers on each arm that make it a "snap" to slide. This product ships in approximately 1 days