The coziest jammies ever! Our shorty zippy one-piece pajama is made from the softest, premium Bamboo Viscose. We've added extra features like a 2-way zipper for easy diaper changes, and no irritating tags for extra comfort for your baby and toddlers. They are super stretchy to allow for longer wear than your standard pajamas, so you can be sure to get maximum use from our Shorty Zipper Romper. * 95% Viscose from Bamboo, 5% Spandex, 220-230 GSM * Two-way YKK zipper * Tight-fitting to comply with CPSC regulations We recommend sizing down from cotton pajama sizing. Model is wearing size 18-24 months and is 32 inches, 28 pounds.