Cotton Imported 100% cotton premium fabric with no added chemicals. Now with two-way zipper and zipper covers at top and bottom. The only 3-way adjustable swaddle that adjusts to your baby's sleep style. Swaddle arms in, hands-to-face, one or both arms out to ensure baby's best sleep and an easy and gentle transition to the SleepSack wearable blanket when it is time to stop swaddling. #1 Choice of hospitals. Used by hospitals nationwide as their swaddle of choice for safe sleep education. "Back is Best" embroidery reminds caregivers to place baby on his or her back. Generous sack design allows room for kicking, but cannot be kicked off so baby stays warm all night. Recognized as "Hip Healthy" by the International Hip Dysplasia Institute. Use over regular sleepwear to take the place of loose blankets. Discontinue swaddling when the baby shows signs of rolling over or breaking out of the swaddle wrap. The original wearable blanket replaces loose blankets in the crib for a safer environment; the 3-way swaddle ensures your baby's best sleep and an easy transition when it's time to stop swaddling; number 1 choice of hospital nurseries to promote safe sleep