The 6 Inch 2-Stage Classic Crib & Toddler Mattress is the Flagship, award winning design. It has an Organic Cotton, water repellent, removable & machine washable cover. This 100% Breathable mattress not only helps regulate temperature by allowing air to pass through the entire mattress, but there are no VOC's, no off-gassing (that chemical smell when you open a mattress with foam), and no toxic emissions. It's designed for extra firm infant support, and a comfortable plush side for your growing toddler. The infant side is made with a firm, durable support. Around the entire perimeter of the mattress, is a 2 inch, firm edge guard to support children as they begin standing. All materials used are eco-friendly, hypoallergenic, and breathable. This mattress is GreenGuard Gold Certified.