Tommee Tippee Closer to Nature Vari-flow Feeding Nipple 2 Pack 423960 is Designed to Adapt to Your Baby's Feeding Pace, Offering Customizable Milk Flow. This Nipple Features a Unique Y-cut That Allows the Baby to Control the Flow, Making It Suitable for Various Stages as They Grow. Its Soft, Breast-like Shape Encourages a Natural Latch, and the Anti-colic Valve Helps Reduce Air Intake. Made From Safe Silicone, These Nipples Are Easy to Clean and Replace, Ensuring Hygienic and Responsive Feeds.