A Safe and Natural Home for your Babe Our Koko Crib Mattress with Wool Layer will create the best environment for your little babe Completely natural, with no harmful chemicals, this firm and lightweight mattress is resistant to dust mites, mildew, and bacteria. Made with a 4 thick layer of coconut husk and coated with natural latex from rubber trees, this mattress has unsurpassed resilience, durability and ventilation properties.The wool layer on both sides provides extra comfort, as well as natural climate control to prevent baby from overheating.