The Sealy Butterfly Posture Support is an American-made all foam newborn crib mattress compressed and shipped in a small box. Designed to “butterfly” out from a roll into a firm flat surface for premium posture support, our foam absorbs motion and maintains its shape for years of use. A zip-on waterproof cover helps to maintain a healthy sleeping surface. CertiPUR-US Certified foam and Greenguard Gold Certified materials.