The HALO SleepSack Swaddle: The Safer Way to SwaddleTM. Its adjustable swaddle wrap immobilizes baby's arms to prevent the Moro or startle reflex. It is the only 2-in-1 adjustable swaddle that allows for swaddling arms in or arms out for baby's comfort. replaces loose blankets in the crib for a safer night's sleep use over regular sleepwear unzips from the bottom for easy diaper changes used in hospitals nationwide and recommended by safety organizations approved as hip healthy by the International Hip Dysplasia Institute back is best embroidery reminds caregivers to place baby on back discontinue swaddling when baby shows signs of rolling over or breaking out of wrap cotton washable imported newborn: 6-12 lbs., small: 13-18 lbs.