This is a warm and cozy sleep sack for wintertime. So cute and soft! It has been through the dryer and as such the wool has a little bit of felting and the zipper is puckered (see photos). Cotton jersey on the outside, merino knit on the inside. See website for full details: https://babyinmerino.com/collections/merino-sleep-sacks-child/products/sleep-sack-with-open-legs-dreamy-stars