Anti-colic baby bottle proven to reduce colic symptoms such as gas, extensive crying, and reflux; Advanced venting system reduces air bubbles One-piece integrated bottle nipple and collar makes bottle preparation and cleanup easy; Fewer pieces than the leading anti-colic bottle based on NPD Unit Sales L52 2021; Includes one vent brush for easy cleaning Unique Y-cut bottle nipple design allows baby to control the flow of milk with their suction strength for comfortable, colic-free feeding; Nipple mimics the shape of mom's nursing nipple, making this a great bottle for breastfed babies SafeTemp indicator shows when milk is too hot Leak-proof, BPA-free, dishwasher-safe bottle nipple; safe for sterilizer and bottle warmers, too NUK Smooth Flow Pro Anti-Colic Baby Bottle features an anti-colic venting system proven to reduce colic symptoms of gas, extensive crying, and reflux. Our newborn bottle has a unique one-piece nipple and collar design to make prep and cleanup easier.