The Safety 1st Grow with Me Dual Sided 2-in-1 Baby Crib & Toddler Bed Mattress is the only mattress you'll need with its unique constructions. It offers your little one with two different levels of firmness: on one side, extra firm support for infants and on the other, additional cushioning for toddlers. This dual-purpose crib and toddler bed mattress is built to last, made with a high-density thermo-bonded fiber core made from polyester fibers and a 100% Polypropylene non-removable outer cover that is waterproof and stain resistant to easily wipe clean in seconds. The Grow With Me 2 in 1 baby crib and toddler mattress is lightweight and durable and fits standard crib with internal measurements of 285/8 in. X 53 in. This Safety 1st mattress is made without the use of flame retardant chemicals and has achieved GREENGUARD Gold certification, meeting the standard for low-chemical emissions for a sleep environment that's always safe and sound. Assembled in Canada, this Safety 1st mattress comes with a 10-year limited warranty.