We like to think of a box spring as the backbone for your mattress. The best kind should be flat, level and built to keep your mattress in tiptop shape; and that’s just what the Smart Box Spring does! With its easily assembled, dependable steel structure, you can rest assured that your mattress will be sitting pretty. An included poly jacquard cover blends with the rest of your bedroom, and with a variety of different thicknesses to choose from, you can pick the one you need to customize the height of the bed. All packed in a compact shipping box with everything included, even our 5-year worry free warranty! Now that’s peace of mind you can sleep on. Features: Steel Interior Frame With Knitted Polyester Cover,THE LAST BOX SPRING YOULL EVER NEED - Unlike a traditional box spring, the Smart box spring is made of solid steel that comes together in no time.,DURABLY ENGINEERED - Durable steel is used to construct the inside framework of this foundation; twin size supports a maximum weight capacity of 350 lbs, while all other sizes can support up to 700 lbs,HIGH PROFILE DESIGN - A 9 inch height is perfect for shorter mattresses or for those who enjoy their bed higher off the floor; For the fastest resolution and to avoid delays, please describe your issue as precisely as possible,THOUGHTFULLY PACKAGED - All parts, tools and instructions are packed into one compact box that ships straight to your door,Worry-free 5 year limited warranty included; box spring only, a bed frame or platform bed is required to support this foundation and is sold separately