The Gel-infused Dough® memory foam cradles the head and neck to relieve pressure, while an ample layer of liquid Z™ Gel captures and distributes heat for a comfortable sleep temperature. It combined the best cooling technologies with a unique shoulder recess that offers superb neck support for side sleepers. A removable 100% Tencel® fiber cover adds softness and moisture-wicking comfort. Cover: 100% Tencel® lyocell, Fill: 100% polyurethane gel foam.