This Super Firm 2 Stage Crib Mattress is dual sided with a super firm side for infants and 2" tencel infused fiber layer on the toddler side for the ultimate sleep comfort. The innovative new airflow cover and mesh borders provide continual 4 way air permeability for better air circulation to help keep baby from overheating. Special breathable waterproof liner around the mattress core to keep it clean and fresh! Lifetime full warranty. | Simmons Beautyrest Crib Mattress, Breeze