FLUTTER FLEX TECHNOLOGY The new "FLUTTER FLEX VENT" System is proven to Reduce Colic, the Flutter Flex Vent technology allows air to flow between the threads of the ring and neck and into the spaces located at the top of the bottle neck. As baby feeds, the air pressure on the inside of the bottle becomes lower than the pressure on the outside of the bottle. This pressure difference causes the inner ring of the teat to flex inward, thereby allowing air to enter the bottle, and thus venting to occur. REVOLUTIONARY TEAT SYSTEM As baby's suckling begins, the teat will flatten to a natural ortho shape conforming to the size and shape of their mouth during feeding allowing individualized memorization. The base of the teat has raised surface bumps that simulate the hardened "teething" surface that develops at the base of a woman's nipple due to repeated breast feeding, assisting in smooth breast to bottle transition when needed.