A complete feeding system for happier babies. Created by a physician, Dr. Brown’s Natural Flow® is the only baby bottle with a patented internal vent system that actually helps promote good health in babies. By eliminating the vacuum and air bubbles, it helps to reduce feeding problems like colic, spit-up, burping and gas. And the positive pressure created by our system is as close to breastfeeding as your baby can get. Quite simply, it looks and works unlike any other bottle.