11" Tranquility Gel Foam Mattress (King with 8" Hardwood Foundation) Designed to support and correctly align your spine so you can relax at night and wake up pain free Advanced Gel infused memory foam helps you sleep cooler and provides improved pressure relief Open cell structure increases air flow, making it breathable and cooler to sleep on More durable than conventional foams used by other companies Performs consistently over long periods of time, ensuring durability and consistency