Continental Sleep 8-Inch Mattress Foundation Split Box Spring, California King, White 8-inch box spring The box spring is available is 8 inch and low profile 5 inch No Assembly Required and ready to use for mattress and box spring foundation Available is all sizes Size Twin 39"X 75" TwinXL 39" x 80" Full 54" x 75" 54" x 80" Queen 60" x 80" King 78" x 80" California king 72" x 84"