ANTI-COLIC BABY BOTTLE VENT BRUSH. Use the small cleaning brush to scrub the internal components in Dr. Brown’s bottle, including vent inserts, reservoir and other difficult to reach places. BABY BOTTLE CLEANING. Easily maneuvers through Dr. Brown’s Internal Vent System. FITS NARROW AND WIDE-NECK BOTTLES. These brushes can be used for all Dr. Brown’s Narrow and Wide-Neck Baby Bottles. Suits most anti-colic baby bottles and other bottle brands. MULTI-PURPOSE AND LIGHTWEIGHT. Versatile cleaning brushes can be used to clean Sippy Cups and Straw Cups. 4-PACK BOTTLE CLEANING KIT. Replace lost or worn brushes that originally came with your baby bottles or keep a few spares with this 4-brush pack.