Sleep Innovations 1-1/2-Inch Memory Foam California King Mattress Topper For improved comfort, circulation, and alignment, 1-1/2-inch high memory foam California king-sized topper; great alternative to mattress purchase In 100-percent polyurethane, hypoallergenic memory foam with 3-pound density; open-cell design for air flow and neutral surface temperature With cotton-polyester blend terry velour cover; reduced size for better fit under sheets After unpacking, allow up to 72 hours for topper to fully expand; also available in twin, full, queen, and king sizes Made in the USA, topper measures 80 inches long by 68 inches wide by 1-1/2 inches deep