60 inch sofa bed. We offer sleeper sofa sheets in the correct sizes and we also offer a choice of mattress depth from up to six inches and up to twelve inches. Get 5 in rewards with club o. First of all this couch from dhp is designed for your small space home that comes with rich linen upholstery and chrome legs. Sleeper sofas require a special size of bed sheets because of the unique size of the mattress and the unique depth.