The first bottle on the market that can be used with or without ventilation. The new ventilation system is designed to grow with your baby. We recommend using it to get all the benefits a bottle can give – it reduces nutritional problems, helps digestion and helps preserve vitamins.Two options – One bottle:1.Using a bottle with a valve: reduces nutrition problems, vitamins in milk are retained, helps digestion.The flap and the nipple make the feeding without air intake2.Using a Bottle without a Valve – Parents find this option very convenient when the baby’s feeding becomes more developed and good.”Dr. Brown’s Bottle-2pcs. Options + Wide-Neck.270 ml – Size 1 pacifierClinically proven to reduce colic, burping and gas by offsetting the negative pressure in the bottle, eliminating vacuum and air bubbles.Featured in the US patented Air Flow internal vent system, which directs the air from the nipple through the tube to the back of the bottle while drinking, bypassing breast milk or formula. Not allowing them to be mixed, minimizes oxidation and helps preserve essential nutrients such as vitamins C, A and E.The new bleeding system is designed to grow with your baby so you can use the bottle from birth to your baby’s birth. Creates a favorable positive pressure similar to breastfeeding.Composition: Polypropylene, Silicone, Santoprene.Does not contain BPA (BPA Free).Recommended age: 0 months +