Dr. Brown's Options line of bottle truly gives parents flexibility.  The internal vent system can be used to help reduce feeding problems and to help with digestion for your baby.  The internal vent can be removed and the bottle can be used without it as well.  

Features:

• Helps reduce feeding problems
• Helps preserve vitamins
• Helps digestion
• Vent and nipple create vacuum-free feeding
• BPA Free
• Includes: Three 9 oz/270 ml Wide-Neck baby bottles, Three Level One Silicone Nipples 0-3 Months, One Cleaning brush