Unyielding supports layered with advanced cooling defines this Serta Perfect Sleeper Cascade Bluff firm hybrid mattress, anchored by the Q4 Support System to balance weight distribution and guard against long-term sagging. Cool Feel technology, paired with a breathable wool layer, maintains a refreshing sleep environment, while EverCool Supreme Hd Memory Foam softens pressure points. Adjustable base compatibility lets you tailor each position for deeper rest.