Dream On Me, Aster 3" Fiber portable crib mattress softly cradles your baby for comfort, the inner core is constructed with extra firm eco-fiber for an inviting, comfortable, for your sleeping baby. The waterproof cover can be easily cleaned with warm water and a mild soap. This mattress is proudly constructed of quality materials and workmanship in the USA. This mattress passes the Federal Standard Flammability Standard 16 CFR 1633. As parents are looking for more space saving furniture, mini and portable cribs are ideal for apartment/ smaller home and Dream On Me Aster mattress fits most mini and portable cribs (not designed for standard cribs or pack 'n plays).