Dr. Brown's uniquely designed Natural Flow Options+ Wide-Neck Y-Cut Nipple is a fast flow nipple, made for use with thicker liquids. The breast-like shape encourages a proper latch for a more natural bottle-feeding experience. 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 Y-Cut Nipple gives baby vacuum-free feeding clinically proven to reduce colic, spit-up, burping, and gas, better preserves nutrients, and aids in digestion for a good night's sleep. While our bottle works best with the vent system, it's great to have options when a baby's feeding develops. Just remove the vent and the feeding experience is similar to most nipple-vented bottles. The suggested age range for the Y-cut nipple is 9 months+ but the baby's preferred flow rate may vary. Fits Dr. Brown?s Options+ Wide-Neck bottles. Dishwasher (top rack) and sterilizer safe. BPA free.