The amazing anti-colic bottle from the Zero.Zero collection (270 ml + medium flow M) is the result of a simple observation of nature and is unique due to its patented anti-colic pouch system. As your baby drinks, the pouch contracts, just like the milk glands in the breast do. This helps to significantly reduce colic and prevent reflux. Additionally, this system also prevents air from oxidizing the milk and destroying the nutrients contained within. It is hygienic and easy to clean, making it the ideal bottle for the first months of your little one, as it allows for natural sucking without colic. The nipple is revolutionary and has been developed based on scientific studies. It is designed to closely resemble the mother's breast in terms of color, soft texture, angle, and length. Babies who are mixed-fed and switch between bottle and breast will not get confused or reject either feeding method. The slit in the nipple allows more or less liquid to flow through depending on how strongly the baby sucks.