The Sealy Baby Ultra Rest comes with 204 American-made posture supportive steel coils that are durability tested for lasting use. Premium 204 coils with secure steel edge frame for ultimate protection along the sides and corners. An anti-sag system keeps the center zone protected for infants. Double layers of hypoallergenic cushioning that is firmness tested for newborns but cozy for growing toddlers. Hospital-grade antibacterial surface. 100% waterproof surface. The lock-stitched waterproof binding. Weighs only 14 pounds to easily lift and change crib sheets. Meets ASTM Crib Mattress standards. Snug fit inside USA standard size cribs and toddler beds. Measures 51.63" L x 27.25" x 5.25". All Sealy crib mattresses are GREENGUARD GOLD Certified for a healthier indoor sleeping environment; the GOLD standard encompasses strict tests for products used with children. Parents trust Sealy as the leading crib mattress brand because it is tested to the highest safety and quality standards. Bring safe, supportive crib mattresses home for your little one with a Sealy Baby product. Passes flammability standards without the use of any flame retardants, passes lead, phthalate and strict chemical test so you can feel confident you've selected the best for baby.