Noah Megatron 7 Inch Heavy Duty Metal Box Spring for King Size Bed Frame :- https://www.amazon.com/Noah-Megatron-Heavy-Metal-Spring/dp/B077DRV9BZ :- You can finally enjoy the strong support, comfort, and convenience with this 7 inch box spring. The boxspring provides a softer and more comfortable sleeping surface than platform beds. Made of heavy duty stainless steel, our box springs prevent the foam mattress from sagging, distribute body weight evenly, which expands the life of your mattress. It’s easy to assemble with the simple tools included with this product and durable to last a lifetime.