Polyester (57.8%), Viscose (42.2%) DUAL-SIDED BABY & TODDLER GROW-WITH-ME MATTRESS: The Ultra 2-in-1 Premium Dual-Sided Baby Crib and Toddler Mattress features a dual-sided design crafted to grow with your child, from the infant stage to the toddler stage. One side is firmer for babies, while the other is softer for toddlers. ULTRA-SOFT, WATERPROOF, MACHINE-WASHABLE COVER: Features an ultra-soft, removable, machine-washable cover with a waterproof sleep surface. Gently unzip the outer cover, wash in cold water (delicate cycle, no bleach), and hang to dry (do not tumble dry) SMARTLY PACKAGED MATTRESS-IN-A-BOX: Delivered compactly to your door for easier handling and setup. Simply unbox and allow up to 48 hours for full expansion — then it’s ready for comfort. GREENGUARD GOLD CERTIFIED — FOR CLEANER INDOOR AIR: GREENGUARD Gold Certified products are low-emitting & contribute to cleaner indoor air for you and your family; Certified products are screened for more than 15,000 VOCs known to pollute indoor air CERTIPUR-US CERTIFIED FOAM — TESTED TO MEET CERTIPUR-US’ RIGOROUS STANDARDS: Flexible polyurethane foam analyzed by independent, accredited testing laboratories to meet CertiPUR-US’ rigorous standards for emissions, content, performance, and durability FITS ALL STANDARD FULL-SIZE BABY CRIBS AND TODDLER BEDS: Designed to fit any standard full-size baby crib and toddler bed (52 in x 28 in). Includes a 10-year limited warranty. GRACO — THE SAFEST PLACE OUTSIDE YOUR ARMS: Manufactured by Storkcraft — the exclusive Graco licensee in North America for nursery and children’s furniture products; Backed by Storkcraft’s supportive Customer Care team and one-year limited warranty MATTRESS DIMENSIONS: Width (28 inches) x Depth (52 inches) x Height (6 inches)