Breast is best, but a time may come when you"ll need to feed baby from a bottle. These Avent 4-ounce bottles feature a wide neck for easy cleaning and filling. The cap seals shut for leakproof mixing and travel; the wide, soft silicone nipple mimics the feel and shape of the breast; and the patented antivacuum skirt valve reduces air swallowing and painful gas. Use these bottles with the Avent Isis manual breast pump to express milk directly into the bottle--no messy filling.Developed in Britain, award-winning Avent bottles more closely simulate the natural feeding process for happier, less colicky babies. The Avent bottle"s broad, soft silicone nipple mimics the shape and feel of the breast so Baby can suckle more naturally. Plus, a patented anti-vacuum valve allows air into the bottle as Baby feeds, so less air is swallowed than with conventional bottles. Wide neck design makes cleaning and filling easier too. Compatible for use with the Avent ISIS breast pump. In 9-oz. or 4-oz. sizes, each with newborn nipples. 3-pk. Imported.Philips Avent 4oz Bottle. The Avent Natural Feeding Bottle is recommended by many doctors. The Natural Feeding Bottle features a nipple with a unique anti-vacuum skirt and one-way air valve that has been clinically demonstrated to reduce colic.