The 2 in 1 Organic Cotton Ultra is highly versatile, combining waterproof and quilted sides for an ideal children's mattress. Use the waterproof side when they first come out of the crib and while they're training. The waterproof side also functions as a dust-mite barrier. When the child gets older, flip the mattress over for a more luxurious comfortable feel. Luxurious organic cotton fabric with easy-to-clean 100% polyethylene waterproof surface (so pure it meets food contact standards). Provides the ultimate non-toxic and stain resistant waterproof mattress cover. Also functions as a dust mite/bed bug barrier - no need for an additional dust mite encasing. Extra strong for long lasting durability with natural color finish. Features a premium 14.5 gauge steel coil innerspring with alternating coil directions. This provides a strong stable feel that is both comfortable and supportive. 6 gauge border wire adds heavy duty edge support for long lasting durability. Twin: 360 Coils. Full: 528 Coils.