Dr. Brown's uniquely designed natural flow options+ wide-neck nipples. The shape of this nipple is designed to be breast-like to better encourage a proper latch for your new baby. Designed alongside medical professionals, the correctly contoured nipple shape and high-grade, soft silicone offer a more comfortable feeding experience and help to avoid nipple confusion. Perfect for switching from breast to bottle and back again! Together with the anti-colic internal vent system, the Wide-Neck Nipple gives baby vacuum-free feeding that is clinically proven to reduce colic, decreases spit-up, burping, and gas, better preserves nutrients, and aids in digestion for a good night's sleep.