Dr. Brown's Natural Flow Options+ Anti-Colic Baby Bottle Gift Set, Blue. This anti-colic baby bottle features a clinically proven internal vent system that reduces colic, spit-up, burping, and wind. It provides a consistent flow rate that is closest to breastfeeding, allowing babies to feed at their own pace. The vent system helps preserve bottle milk nutrients and aids in digestion for a better night's sleep. The breast-like nipple teat encourages a proper latch for a more natural bottle feeding experience, easing the transition from breast to bottle and back again. Dr. Brown’s Natural Flow Anti-Colic Options+ baby bottle works best with the internal vent system in place but can be removed as baby’s feeding develops, eliminating the need to introduce a different bottle.