Sleep cool and comfortable with the Little Sleepery 5-Inch Twin XL Memory Foam Mattress. Designed exclusively for Max & Lily bunks, lofts, and beds, this Little Sleepery mattress is the perfect fit for growing sleepers and their setups. The innovative four-layer design combines superior breathability with the plush feel and medium-firm support that’s perfect for younger ages. Little Sleepery’s compact comfort construction provides all the comfort of a 10-inch twin xl mattress without the bulk, maximizing headroom on bunks and lofts and making it easier to make the bed. This low-profile twin xl mattress provides extra headroom and guard rail space on bunk beds and loft beds. The top layer of Comfort Cushion Memory Foam provides a delicate, sink-in feel without sagging. The memory foam layer cradles your body and conforms to your sleeping position, reducing motion throughout the night. The Comfort Support layer provides the perfect balance between plush and firm. The high-density Hero Layer improves sleep posture while eliminating the need for a box spring or Bunkie board. A layer of Dynamic Support Base Foam provides extra durability and structure to the twin xl size mattress. The breathable mattress cover is made with an anti-microbial cotton blend for a comfortable, plush feel. Anti-microbial cotton blend also provides the mattress liner a safe, fire-retardant design without the use of fiberglass and chemicals. This twin xl mattress for kids is anti-bacterial to keep your sleeping space cleaner and fresher for longer. This CertiPUR-US certified, hypoallergenic kids twin xl mattress is made with non-toxic, eco-friendly materials and is low VOC, contributing to a clean and healthy sleeping space in your home. Little Sleepery memory foam mattress is made without the use of formaldehyde, mercury and other heavy metals. This mattress in a box comes compressed and rolled for an easy setup. We recommend letting the 5-inch twin xl mattress air out and reshape for 24 hours before use. This Little Sleepery kids' mattress is designed to work perfectly with Max & Lily bunks, lofts, and beds – providing enhanced breathability and longevity when paired with wood slats. We cannot guarantee this twin xl size mattress will fit trundle beds from other brands.