At the very top of this mattress lies the fabric cover – featuring stretchable material and upholstered sides. Available in Single, Double, King and Super king sizes. The top layer of the Casper is the comfort layer. It’s also removable, which makes for easy washing. These options include air mattresses intended for outdoor use and camping. Costco is an online-only furniture retailer that sells mattresses in addition to other types of home furnishings. shrls_str_117 = shrls_str_117+'