The Philips Avent Natural Response nipple only releases milk when the baby actively drinks. Babies can therefore drink, swallow, and breathe using their natural rhythm, like on the breast \u2013 making it easy to combine breast and bottle-feeding. This bottle has a unique nipple opening which only releases milk when the baby actively drinks \u2013 so when they pause to swallow and breathe, the milk pauses too. The wide, soft, and flexible nipple of the Avent bottle is designed to mimic the shape and feel of a breast, helping the baby to latch on and feed comfortably. Additionally, the anti-colic bottle value is designed to keep air away from your baby\u2019s tummy during feeding, to help reduce colic and discomfort. The ergonomic Philips Avent baby bottle is easy to grip at any angle to give maximum comfort during feeding \u2013 easy for both your hands, and tiny hands, to hold! Every baby feeds differently, and develops at their own pace. We\u2019ve designed a range of flow rates so.