Nesties come in 4 components, the mattress, the ‘wall’, a mattress cover and a ‘wall’ cover. The interior wall  is made from water repellent wipe clean polyester and the base is made from wipe clean 1000 denier Cordura,  the covers are made using polar Fleece. There is no Velcro or press studs - a length of elastic and a toggle keeps the cover in place. The ‘wall’ and mattress are stuffed in individual sections, which ensures the sides stay stable and do not collapse.