Tommee Tippee Advanced Anti- Colic Bottles have a unique anti-colic venting system. Plus, the venting tube comes with a built-in heat sensing strip that gives you extra reassurance that milk is not too hot for a comfortable feed. The anti-colic teat also flexes and stretches like mum's breast, to ensure a natural latch and feeding experience. Unique venting system designed to prevent colic. Babies may develop colic symptoms if they take in too much air during feeding. With its unique anti-colic venting system, Tommee Tippee's Advanced anti-colic baby bottle helps stop air mixing with milk. Air is drawn through the vents in the venting wheel, down the venting tube and out of the star valve at the base of the bottle, this means 80% fewer colic symptoms, such as wind, reflux and fussing, meaning you can feel relaxed knowing your baby is enjoying their feed. The venting tube has a heat sensing strip that changes colour if milk is too hot. Dip the tube for 10 seconds to see the feed's tem.