With the Hybrid 1100 California king mattress, you have endless possibilities for restful sleep. Feel the support of a truly traditional coil mattress which contours to your body for a comforting feel. High-density foam provides the firmness you love. Convoluted comfort foam provides added air flow, keeping you cool and comfortable while alleviating aches and pains. This mattress arrives in a box for quick and easy setup. Simply remove the plastic wrap and unroll. Foundation/box spring available, sold separately.