The AirFree™ vent is designed to help your baby swallow less air. The teat stays full of milk, even when horizontal, for upright feeding. Reducing the air a baby ingests can help ease common feeding issues like colic, gas and reflux.Clinical studies have shown that the Philips Avent bottle reduces colic and fussing*. In addition, the valve in the teat prevents vacuum build-up. This means that the air stays in the bottle, away from your baby's tummy.The AirFree™ vent is a single piece compatible with any Philips Avent Anti-colic and Classic+ bottle. Cleaning is also a breeze, as the bottle has a wide neck and there are only a few parts to clean.To start, fill the bottle with milk, place the AirFree™ vent over the rim, and screw on the teat. Tilt the bottle downwards once to fill the teat, and you're ready to go. When feeding, make sure that the AirFree™ vent stays on top. The teat will stay full of milk, even when it's horizontal, for easier upright feeding.As your baby grows, their needs change when it comes to drinking. Choose a teat with a flow rate that's right for their development. They can be used with Philips Avent Anti-colic and Classic+ teats.We designed our Anti-colic bottle range so it's easy to mix and match tops and bottoms. This way you can progress easily from bottle to training cup to sippy cup, with fewer parts.