If you're looking for a full size mattress or a twin mattress of great quality, then Costco is worth a visit. Costco carries a very nice selection of full size and twin mattresses by Sealy among other brands. These mattresses feature memory foam quilt layers, Alignment Zone technology and silk/wool layers that provide an extra pillowy sleep surface. All of these beds are very comfortable and durable. So if you're looking to purchase a bed to last for many years to come, then a Sealy mattress from Costco is a great choice. At Costco, you can find a wide selection of furniture for all rooms of the house as well as bathroom products and building materials. 
Sterlingshire Twin
"The Sterlingshire Firm Twin mattress offers a firm, yet comfortable sleep surface. The firmest Sealy Posturepedic mattress in our Sealy product line available at Costco.com. Luxurious knit cover. 1 oz. FlameGuard. FiberLux Fiber. 1" Memory Foam. ½” Sealy Foam"
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Whitby Full
"The Whitby Plush Full Mattress Set offers a comfortable sleep surface that conforms to the body. Top quality Damask cover. 1 oz. FlameGuard FiberLux Fiber. 2 Layers ½” SuperSoft Sealy Foam" | 
Sedona Springs Full
"The Sedona Springs Ultra Plush Full mattress offers a comfortable memory foam sleep surface that conforms to the body. A softer feel than the firm, but not as soft as a pillowtop. 14 gauge Posturepedic coil unit. Mattress thickness: 13”. Shock Abzzorber Plus box spring. Box spring thickness: 9"" | 
Whitby Twin
"The Whitby Plush Twin Mattress Set offers a comfortable sleep surface that conforms to the body. 1 ½” x ½” SculptureFoam, 2” x 1” Pressure Point Foam. Comfort Support System. Inner-Tufted" |
These mattresses can be found at costco.com
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