Selby's XSMVO wall bed system for twin and single sized mattresses makes turning an office, den or any other room into a spare bedroom. We supply the hardware and all you do is build a wooden frame for the mattress (mattress not included) and any cabinetry you need to hide the bed. Similar to a murphy bed hardware system, these fold away bed units come in two versions; one with the hardware exposed and one with the hardware concealed. The load ratings, 110 lbs or 240 lbs, refer to the total weight of the frame, hardware, mattress and bedding combined. The spring tension is adjustable so you can get just the right lift for closing the hidden bed.