This gel-infused memory foam pillow earned The Best rating from the Hammacher Schlemmer Institute because it stayed cool the longest. Unlike other tested pillows that increased in temperature by 23.32% over an eight-hour period, The Best model only increased in temperature by 17.54% thanks to its dual-sided cooling gel construction. The ventilated, two-sided gel memory foam overlay and memory foam core is engineered to absorb excess heat from a sleeper’s head. Built-up heat is dissipated through breathable, vented sides. The memory foam core provides pressure-relieving support and comfort and recovers its cooling properties as you shift positions during the night. The circular-knit hypoallergenic, comfortable polyester cover helps to eliminate odors and removes for easy spot cleaning. 23" W x 5" H x 16" D. (4 lbs.)