The 13 in. Hybrid Mattress is purpose-built for restorative sleep, integrating advanced cooling solutions, targeted pressure relief, and long-lasting support. It relies on Dual Cooling Technology (with phase-change material) and two layers of Tempa Gel (including the enhanced Generation II) to absorb and release heat, ensuring a consistently cool sleep environment throughout the night. Complemented by DuraLast Foam (for shape retention), the exclusive Marvelous Middle (25% extra lumbar support plus reduced motion transfer), and a 1000-individually wrapped coil system (360° Super Edge for stable edges), this 13 in. mattress strikes the ideal balance between cooling comfort and firm support-helping users wake up feeling refreshed. Size: california king.