Natural Flow®Clinically Proven To Reduce Colic, Spit-Up, Burping, and Gas Baby's First Step To Sippy CupNarrow - 3 BPA FreeUse With Or Without Vent  Contents:  1 - 8 oz/250 ml bottle1 - Level 3 silicone nipple1 - Sippy spout1 - Cleaning brushInstructions  A sustainable bottle for a sustainable world. Our bottle is designed to nourish through all of baby's feeding stages.  Vent system is proven to: reduce colicpreserve vitaminspromote better sleepsupport breastfeeding Remove vent baby feeds freely no need to introduce a different bottle. Designed to grow with baby.  Start with baby steps ... Ease the transition from bottle to cup with Dr. Brown's® Bottle to Sippy Starter Kit  Take the bottle baby loves and simply replace the nipple with the super-soft silicone spout for the very first step toward a sippy cup.  Remove vent and nipple to transition to sippy spout.