The Anti-Colic Baby Bottle with AirFree vent was specifically designed to reduce reduce colic, gas and reflux Philips Avent Essentials Set is the ideal set to get started with bottle feeding. It helps new parents keep up with baby's growing appetite. Our unique AirFree vent is designed to help your baby swallow less air as they drink by keeping the nipple full of milk during feeding. Reducing the amount of air your baby ingests helps with common feeding issues such as colic, reflux & gas. Products are BPA free. Nipple stays full of milk, not air - The nipple stays full even when the bottle is horizontal, so your baby can drink in an upright position. This can help reduce reflux, aid digestion, and make feeding time more comfortable for you and your little one. Nipple shape designed for a secure latch - The shape of the nipple allows for a secure latch, and the ribbed texture helps prevent nipple collapse, for uninterrupted, comfortable feeding. Easy to clean - With its wide neck and fewer parts, our bottle is easy to assemble and to clean quickly and thoroughly. Different nipple flow rates available - Different flow rates to keep up with your baby's growth. The Philips Avent Anti-colic bottles can be used with or without the AirFree vent—but they should only be used with Philips Avent Anti-colic nipples.