Dream Serenity 3 Cool Breeze Memory Support Mattress Topper, King King: 78" x 74" x 1.5" Cool support, gel-infused memory foam Advanced CoolFlow technology Ceramic gel beads help keep foam cool throughout the night Gentle pressure-point relief Unique balanced support All foam used in this product carries the CertiPUR-US seal Allow 24 to 48 hours for foam to expand Easy-on, easy-off breathable knit cover with elastic for custom fit and is machine-washable Dimensions of toppers are made slightly smaller than mattresses to ensure proper fit