Coverall is made of 95% Viscose from Bamboo, 5% Spandex. Diaper checks are a breeze thanks to the swell back flap that snaps open for easy access. SPF 50+. KicKee Pants uses only source bamboo that is grown organically from manufacturers that provide Harmful Chemical Free Assurance. Sizes 9 months and below are layette fit which is a looser fit designed for the comfort of young babies.