Breathable – This crib mattress features a dual-sided Air-X breathable cushion for maximum airflow around and under your baby. Dual-Sided –This durable 2-stage convertible crib mattress has a safe, firm surface on the infant (0-12 Months) side, with a softer and responsive surface on the toddler side (12 months and up). Sleep Clean and Healthy – The Air-X 2-Stage Crib Mattress is hypoallergenic, ensuring a clean and healthy sleep each night. Removable and washable cover provides a safe and clean sleep environment BEDGEAR crib mattresses are are CertiPUR-US Certified and GREENGUARD Gold certified providing trustworthy performance for your little one. Dimensions – 52” L x 27 ¾” W x 6” H