Baby can learn new straw sipping skills while continuing to use the bottle they love with Dr. Brown’s® Wide-Neck Sippy Straw Bottle Conversion Kit. The Sippy Straw and Flip-Top Cap can be used in place of the baby bottle nipple on Dr. Brown’s® Options+® Wide-Neck 9 oz/270 mL baby bottles and sippy spout bottles when the internal vent system has been removed. The sliding Flip-Top Cap helps keep messes contained when closed and makes spill-proof travel a breeze! The included Cleaning Brush allows for easy cleaning in hard-to-reach places, like the inside of the straw. Sippy Straws and Flip-Top Caps are dishwasher (top rack only) and sterilizer safe.