The Silentnight Healthy Growth Miracoil Sprung Mattress is a wonderfully supportive mattress designed for growing bodies. The Miracoil spring support system distributes weight evenly and aligns the spine as your child sleeps. Hypoallergenic and breathable Eco Comfort Fibresâ„¢ allow air to circulate freely around the mattress, keeping them cool and fresh as they sleep. Every mattress purchased also prevents discarded plastic from entering landfills or the ocean. With a Five Year Guarantee and Free Next Day Delivery, don't wait to upgrade your child's sleep.