Step-up of Chicco Teat Two anti-colic vents are part of Normal Flow configuration. These vents shield your infant from air inhalation during feedings, reducing the risk to them. Step-up of Chicco Teat Normal Flow includes the infant's natural sucking, as does the mother. Constantly full of milk, less air is swallowed promotes a newborn's proper neck position The teat's elasticity and flexibility are increased by flexors at its base, which mimic a mother's breast.