Clinically proven to reduce colic and discomfort Anti-colic valve integrated into the nipple vents air into the bottle and away from baby's tummy. Designed to reduce gas and fussiness Only 3 parts for quick and easy cleaning and simple assembly A range of flow rates are available for your growing baby. This bottle includes a 1Month+ Slow Flow nipple Trusted by millions of moms since 1984, Philips Avent is the #1 brand recommended by moms worldwide BPA-Free