Thanks for helping us help kids - part of the profits from our We Heart Monsters long johns will be given to organizations that help support kids in need. Because we love earth friendly fabrics, all of our long johns are made from 100% organically grown cotton in our wonderfully soft ribbknit. To make sure kids won't feel anything but the softness of this beautiful combed cotton knit, we use smooth flatlock seams, which are also the most durable we offer. Ready-to-grow cuffs keep the fit neatly in place while stretch waists are great for every age. Certified by Oeko-Tex Standard 100. Wear snug fitting; not flame resistant. Please use the sleepwear size chart. Imported.