This WASHABLE WOOL keeps baby dry and comfortable; protects the mattress. Use it in the bassinet, and later in the crib. GREAT for travel. our wool is never bleached, carbonized, dyed, or treated. Chemical free and repels moisture without rubber or plastic. Sustainable, biodegradable material. Virgin wool is naturally flame resistant. responds to baby's temperature winter or summer, allows air to circulate, keeping your child comfortable always. Durable, long lasting, great moisture barrier and eco-friendly too!