This organic mattress is a perfect choice for young children who are transitioning from a crib to their first “big” bed. The 2-in-1 Ultra combines a certified organic outer cover with non-toxic polyethylene waterproof coating on the top and sides of the mattress and a non-waterproof side made with certified organic cotton quilting. The mattress provides orthopedic medium/firm support with 6 gauge wire providing firm support to the edges. The innerspring contains 14.5 gauge coil steel innersprings. Twin: 360 coils Full:528 coils. Once your child is potty trained you can use the plusher, non-waterproof side until they head off to college. Why Naturepedic? Naturepedic designs all their mattresses to be completely hypoallergenic, they do not contain any latex or wool. This makes the Naturepedic line of organic mattresses a good choice for people who have wool allergies, are chemically sensitive, or unable to tolerate latex. While other organic innerspring mattresses use wool as the flame retardant, Naturepedic does not. Organic cotton is significantly less flammable than polyurethane foam. Specifically, Naturepedic mattresses are built from organic cotton fabric and batting, pla (plant based fiber) batting, and steel innersprings. Their materials smolder rather than burst into flames. Naturepedic mattresses meet all Federal and State flammability standards without the need for any toxic fire retardant chemicals. 10 Year Limited Warranty Proudly made in the USA.