After baby has fully transitioned from swaddling, and the Moro (startle) reflex has faded, and baby can roll over, experts recommend a wearable blanket for sleep. The zzZipMe Sack features a handy 2-way zipper that makes our sleep sack easy to use. It’s easy to place baby in the sack when unzipped from the top and keeps baby warm during diaper changes when you zip up from the bottom. Our award winning design is available in six fabric choices so you can choose the best option for your environment.