With this light and breathable Muslin Bedtime sleep sack will keep your baby's temperature just right for summer nights. With a bottom-to-top zipper, it's a cinch to put on a wiggly baby. Made from premium, open-weave cotton muslin, the cozy Sleeper gets even softer with each wash, and is gentle on your baby's skin. Matches the Snuggle Blanket, Swaddle Blankets, and Car Seat Cover in this pattern.