The Eco Core Organic 2-Stage Dual-Sided Crib Mattress provides 2-Stage support. One side provides a firm sleep surface to support babies up to 12 months of age and one side provides a softer sleep surface for toddlers. Provides enhanced support and an organic cover for an extra touch of goodness. Our crib mattresses are designed to help little ones sleep safe and sound. We start with an eco-friendly, poly fiber core and cover it with a completely hygienic, easy-to-clean cover.