The Philips AVENT Newborn Starter Set includes 2 x 125 ml/4 oz feeding bottles and 2 x 260 ml/ 9 oz BPA-Free Feeding Bottles in addition to a newborn soother and a bottle and teat brush. The Philips AVENT feeding Bottle is designed to work with your baby's natural feeding rhythm. The teat helps your baby to control milk as she would do at the breast, making it easy to feed with a bottle only, or combine bottle and breastfeeding. Philips AVENT bottles are clinically proven to reduce painful colic and discomfort after feeding.The two piece anti-colic system consists of the AVENT Teat and adapter ring. As baby feeds, the unique skirt on the AVENT Teat flexes to allow air into the bottle instead of baby's tummy. Five different teat flow rates are available.