From Naturepedic, this mattress cover features: The Naturepedic breathable pad is a washable, waterproof, breathable pad that can be added to any standard crib mattress. Add an extra layer of breathability to your baby's crib mattress with the Naturepedic Organic Breathable Crib Cover. It combines organic cotton fiber and a breathable mesh pad to maximize airflow for your baby. Breathable layer between the baby and the mattress Breathable layer is waterproof and removable Organic cotton surface Full breathability with full hygiene Make any crib mattress breathable The cover features a soft, GOTS certified organic cotton face and a 3-dimensional polyester lattice structure that creates a breathable space under your baby for increased airflow This results in improved temperature regulation for less sweaty backs and a reduced risk of overheating It also allows the baby to breathe directly through the breathable cover if necessary Waterproof backing acts as a built-in mattress protector No harmful chemicals and no flame retardants No toxic chemical odors/smells Machine washable GREENGUARD Gold Certified Made Safe Certified No vinyl, phthalates, polyurethane foam, flame retardant chemicals or barriers, formaldehyde, pesticides, GMO's, glues/adhesives, etc. TOP FABRIC: Organic cotton | BOTTOM FABRIC: Polyester WATERPROOFING: GOTS approved polyurethane barrier CRIB SIZE (27.5" x 51.875" x 6") Sewn and finished in the U.S.A. with imported fabric