30 years committed to breastfeeding. 8 oz. Without BPA. Reduces gas. With micro air vents. Best for baby. CustomFlow nipple adjusts to baby's pressure. Micro Air Vents keep air out of baby's tummy. Soft and flexible, CustomFlow nipples sense baby’s pressure and respond with the right amount of liquid. Micro Air Vents help to prevent or reduce nipple collapse and minimize air ingestion. CustomFlow nipples come in Slow, Medium and Fast flow to meet your baby's changing needs. Works with Comfi, Classic and Comfort Select bottles. Made in Mexico.