Get your beauty rest with a king-size memory foam mattress topper on your bed. Memory foam conforms to your body, creating a custom cradling feeling for softness and comfort. Add the topper to an older mattress to renew its comfort, or add it to a newer mattress for an extra layer of cushioning. Protect your new mattress topper with a Simmons Beautyrest model featuring a water-resistant cover to keep the memory foam dry and stain-free. An antimicrobial topper from Comfort Dreams lets you sleep without irritation by minimizing dust mites and other microbes. Maintain a comfortable sleeping temperature with a cooling gel memory foam mattress from Serta. A sculpted memory foam topper from Broyhill provides increased support and pressure relief while improving airflow through the topper. Improve the comfort of your king-size bed while staying cool with a memory foam topper from Overstock.com.