The Tempur-Flat Foundation gives a Tempur-Pedic mattress the solid, level surface it needs. Choose the 9-inch high profile for a traditional bed height or the 5-inch low profile to keep a tall mattress from sitting too high. Use it on a bed frame or with a bed skirt in place of a box spring; Tempur-Pedic mattresses should never go on springs. Details High profile 9 inches or low profile 5 inches Rigid, non-flexing foundation built for memory-foam mattresses King and Cal King ship as two pieces Weight capacity 400 lb per Twin/Split piece, 800 lb Queen and larger Compatible with Tempur-Pedic and Stearns & Foster mattresses Why You’ll Love It The correct support for a Tempur-Pedic mattress and its warranty Two heights so you can set the finished bed height you want Two-piece King sizes are easier to move upstairs Sizes & Dimensions Twin 38 in × 74 in Twin XL 38 in × 80 in Full 53 in × 74 in Queen 60 in × 80 in King 38 in × 80 in, two pieces Cal King 36 in × 84 in, two pieces