This baby sleeping bag keeps baby warm when feeding or comforting. Baby is less likely to wake up from kicking off covers. It also helps baby feel secure in unfamiliar surroundings and unzips from the bottom, ideal for changing baby in the middle of the night. Removes the risk of baby getting tangled up in bedding. The sleeping bag is lined in soft 100% cotton jersey with fully enclosed seams - so no rough edges. Allows baby to move arms and legs freely. Outer and lining: 80% cotton, 20% polyester. Filling: 100% polyester.