This Dr Brown"s baby product is BPA (Bisophenol-A) free.Reduces ColicPatented vent system eliminates the vacuum and air bubbles to help reduce colic, spit-up, burping and gas.BPA, PVC, Lead, Phthalate FreeContents3 - 4 oz standard Propylene baby bottles3 - Level-One silicone nipples3 - Two-piece patented internal vents1 - Cleaning brushInstructionsPatented Internal Vent SystemEliminates the negative pressure and excess air ingestionThe patented Natural Flow internal vent system is the only vent that eliminates the vacuum and the air bubbles found in most baby bottles. It allows air to enter through the nipple collar without being incorporated into the breast milk or formula.The air is then channeled though the internal vent system to the area above the breast milk or formula.Babies feed more comfortably because the vent allows them to nurse without fighting the negative effects of a vacuum or the discomfort of ingesting air bubbles. This helps to reduce colic, spit-up, burping and gas.The breast milk or formula flows freely through the nipples as the air is channeled to the top of the bottle. This positive pressure eliminates nipple collapse, and can help reduce build up of fluid in baby"s ear.Unique internal vent eliminates the vacuum and air bubbles to help reduce colic, spit-up, burping and gasBy eliminating the negative pressure, it can help reduce build up of fluid in baby"s earPositive-pressure design mimics breastfeeding and is ideal for breast milk and formula alikeMade in the USA