The rounded shape of the Adiri Natural Nurser is designed to mimic a mother’s breast. This helps reduce nipple confusion and helps baby’s transition to bottle feeding easier. The body and nipple are all one piece. You fill the bottle from the bottom making them easy to use and easy to clean. The Adiri Natural Nurser is wonderfully designed without Bisphenol-A (BPA) so no evil chemicals to worry about. The Nurser is recommended by experts: doctors, nurses, and lactation consultants. A natural and easy way to start bottle feeding.