Dr Brown’s Wide Neck Bottles are created with a unique two-piece internal vent mechanism for vacuum-free feedings. This is also known as positive pressure flow feeding, similar to breastfeeding. During feeds, air is channeled from the teat collar through the vent system to the back of the bottle. The air circumvents the breast milk or formula and minimizes oxidation. In addition, the essential nutrients of the feed like vitamins A, C and E are preserved. As babies don’t have to fight the discomfort of ingesting air bubbles, feeds are longer and easier.