Dr. Browns Options: The markets first convertible bottle that can be used with or without the vent system. The new vent system is designed to grow with baby, and we recommend using this system to experience all the health benefits of our bottle. It helps reduce feeding problems, helps digestion and helps preserve vitamins. Some moms and dads find removing the vent a convenient option as their babys feeding becomes more developed. The nipple venting creates a paced flow, and provides a feeding experience similar to most nipple-vented bottles. Options bottles are BPA-free and made in the USA. Includes Level 3 Nipple for babies 9 months and 1 Sippy Spout to help baby transition from bottle to cup. Super-soft silicone spout is easy to drink from and spill-proof when not in use. Sippy Spout fits Dr. Browns Wide Neck Options Bottles.