The Bundle of Dreams Classic Crib Mattress is a 6 Inch 2-Stage mattress featuring a plush, waterproof, machine-washable Organic Cotton cover. Its 100% Breathable design helps to circulate air and reduce VOCs and off-gassing, while a 2 inch firm edge guard around the perimeter helps children stand safely. GreenGuard Gold Certified, this hypoallergenic mattress is the perfect combination of firmness and comfort.