The choo choo comfy mattress is especially created for kids keeping their comfort in mind using a boundary made of reflex foam around a bonnell springs to prevent your children from rolling off the mattress while they sleep the traditional coil spring system is used to give additional comfort specification 15cm thickness double jersey fabric graphics on the cover ideal for bunk beds high sleeper and mid sleeper made in the uk to british standards and regulations mattress size single 3ft w90