Silicone Integrated Airflex Venting value helps reduce colic and discomfort Newborn Flow is the slowest Flow rate in the Classic+ nipple range - ideal for newborns and breastfed babies of all ages Compatible with all Philips Avent Classic+ baby bottles Made of soft silicone, BPA free Dishwasher safe BPA-Free and made of soft, durable, flavorless silicone Clinically proven to reduce colic and discomfort Anti colic valve promotes active feeding with less air in baby's tummy to reduce fussiness and colic Nipple features 1 hole ideal for newborns and breastfed babies of all ages Includes 2 Newborn Flow Nipples