This Jersey Sleeping Bag is a baby and toddler sleeping bag designed for arms-out sleepers (usually from around 3 months of age). The Jersey Bag has a slim-fit, stretchy design similar to that of a swaddle and is recommended as baby's 'first sleeping bag' after the swaddling phase is over. The safe-sleep approved design is made from soft, stretchy GOTS certified organic cotton that is non-toxic and gentle of baby's skin. The ergonomically designed bag features a bell-shaped bottom to promote healthy hip joint development and is approved by the International Hip Dysplasia Institute, and the material is stretchy to allow baby to move more freely and stay comfortable while they sleep.