The DaVinci Complete Slumber Waterproof Mini Crib Mattress is designed with high-density polyester fiber fill for an extra firm sleeping surface that is GREENGUARD Gold certified, so your baby can sleep safely and comfortably. Parents can easily change crib sheets with this ultra-lightweight mattress that weighs only 3.75 lbs! This mattress features a waterproof, tear-resistant cover that will stay new through years of use.