Philips Avent AirFree Vent Baby Bottle Newborn Gift Set - 4 Baby Milk Bottles with Air-Free Vent, Ultra-Soft Pacifier and Bottle Brush, Babies Aged 0-12 months. Provides calm, comfortable feeds. The Natural Response Teat supports baby's unique drinking rhythm, while the AirFree vent is designed for extra protection against colic, gas and reflux. The Philips Avent baby bottle nipple helps the baby to latch on and feed comfortably. Works like the breast: The teat releases milk when baby actively drinks, this is different from the traditional free-flow teats. As with breastfeeding, it can take time for a baby to get used to this. AirFree vent: This Avent Bottle prevents air from getting into your little one's tummy whilst feeding upright. Right nipple flow: Find your baby's perfect flow rate and personalise your Avent bottle No-drip nipple: The bottle-feeding nipple only opens to release milk when the baby is feeding.