Beautyrest Silver Standard Box Spring - Queen Size A beginner Includes ten Year Limited Warranty, Sleep in comfort with our Simmons BeautyRest Silver Standard Boxspring 9 Inch that provides stable and strong support for all Beautyrest mattresses. This standard profile foundation helps prevent sagging and bowing for the life of the mattress when used with a supportive bedframe. It's constructed with high grade wood and steel struts featuring an exclusive center power beam to reinforce the span in the middle of the foundation. Standard Box Spring Foundation, Boxspring Foundation For The Mattress of yours, Standard Height 9 Height, Center Power Beam, High Grade Wood Steel Strut Construction, Provides Superior Support For all Mattresses, Extends The life Of your respective Mattress