Polyester BREATHE-THRU SAFETY: The ONLY crib mattress with a Wovenaire breathe-thru core. Our patented technology ensures optimal breathability, reducing the risk of suffocation and overheating. And because your baby is sleeping safe and sound, you’ll sleep better too. Measures 52" x 28" x 4". Core proudly made in the USA. COMPLETELY WASHABLE: The crib mattress that’s completely washable from cover to removable core. Easily wash away accidents, dust mites and allergens for a cleaner, healthier, hypoallergenic sleep. Simply throw the cover in the wash and rinse the core in the shower or tub. BETTER, LONGER SLEEP FOR BABY: Babies sleep longer on Newton. And they sleep better too. Our essential crib mattress provides optimal air circulation (cooler sleep!), firm support and incredible comfort, alleviating some of the key sources of discomfort and frequent wakings. *Based on independent testing. GREENGUARD GOLD CERTIFIED: Our mattress is independently tested and certified for low emissions, exceeding the highest industry safety standards to help improve indoor air quality. Your baby will breathe easy, and you can too. INFANT & TODDLER (2-STAGE): One to grow on! Our 2-stage mattress provides your little one with the comfort and firm support they need, all the way through the toddler years. The Newton Baby Crib Mattress is designed to help your baby sleep safely—and help you sleep better, too. At the core is our Wovenaire material: 90% air, 10% food-grade polymer. It's fully breathable and washable, creating a cleaner, safer sleep surface from day one.The dual-layer, breathe-thru cover features a soft, quilted cloud pattern and is machine washable for easy cleanup. Inside, a viscose inner encasement helps meet strict flammability standards. GREENGUARD Gold Certified for low emissions. Firm enough for proper development and comfortable enough for longer sleep stretches. Fits all standard U.S. cribs.