Details:The All in One set to welcome baby to the family. It includes the Philips Avent Anti-colic with AirFree vent bottles, which are designed to reduce feeding issues: such as colic, gas, and reflux. The unique AirFree vent is designed to draw air away from the nipple keeping it full of milk to avoid air ingestion. This vent also keeps the nipple full of milk even when the bottle is held horizontal, allowing for upright feeding. Feeding in an upright position can help to reduce reflux and aid in digestion. The nipple shape is designed for a secure latch for a comfortable feed. The bottle is easy to clean and assemble with few parts. The AirFree vent is only one piece and is easy to clean without any special tools. The Anti-colic bottle features a valve, integrated into the nipple, that reduces vacuum buildup and reducing air into your baby’s tummy. Four sealing discs included to turn the bottles into storage containers, store and feed from the same container.