If you want to buy a Split-King mattress, buy two TwinXL mattresses and select the firmness for each. To learn more, read our article here. Twinkle Comfort PLUS Hybrid is designed for sleepers who crave adaptive support and exceptional cooling in a balanced, durable design. This mattress combines Copper Bounce and Twinkle Bounce™ technologies to give you a medium-firm feel that's responsive yet supportive-perfect for maintaining comfort through every position change.The standout layer of Twinkle Copper Bounce Foam™ adapts instantly to your body's shape, offering just the right "bounce-back" and cushioning pressure relief for shoulders, hips, and spine alignment. This exclusive copper-infused foam adds antimicrobial protection and enhances airflow for a clean, cool sleep environment. Unlike standard foam, Twinkle Copper Bounce Foam™ actively dissipates heat away from the body, making it ideal for hot sleepers.The Twinkle Comfort PLUS Hybrid is built on a supportive pocketed coil system that responds independently to your movements, promoting spinal alignment and reducing motion transfer. This zoned coil layer provides targeted support where it's needed most while keeping the edges firm, so the entire sleep surface feels spacious and stable.Encased in a premium CoolTouch Temperature-Regulating Cover that uses advanced cooling fibers, the Comfort PLUS mattress keeps you feeling fresh all night long. The breathable layers beneath this cover work with the coil system to ensure consistent airflow and temperature regulation, helping you stay comfortable in any season.The Comfort PLUS Hybrid mattress uses Twinkle Bounce™ technology for a resilient, flexible feel, making it a versatile choice for sleepers who prioritize comfort, durability, and cooling performance.With the Twinkle Comfort PLUS Hybrid, enjoy the synergy of cooling comfort, adaptive support, and resilient bounce for a sleep experience designed to refresh and rejuvenate.Mattress height: 13"