Question: what are the avent nipple sizes?
Answer: Nipples are available for 0m, 0m+, 1m+, 3m+ and 6m+. See image below for an overview. These Philips Avent Natural nipples can be used on the Natural Philips Avent feeding bottle and Philips Avent storage cups. The Natural First Flow nipple (with the number 0 on the nipple) is recommended for newborns and preemies.