The Dr. Brown's Natural Flow Anti-Colic Options+ Wide-Neck Sippy Bottle Bundle includes two 9oz/270mL starter kits with level 3 medium-fast flow nipples and 100% silicone soft sippy spouts to help babies transition from bottle to cup. The familiar Dr. Brown's bottle design combined with the easy-to-attach silicone sippy spout allows babies to learn new drinking skills with the products they already know and love. Both sippy starter kits feature a snap-on cap to keep spouts clean on-the-go. As your little one grows, simply remove the anti-colic vent system and replace the nipple with the soft sippy spout using the convenient nipple-to-sippy conversion kit. With two identical 9oz/270mL sippy bottles in complementary colors, this bundle has everything you need to introduce sippy cups while reducing messy spills during the transition process. All parts are BPA free and safe for dishwashers, sterilizers, and boiling water to make cleaning a breeze.