For Ages 0-3 Months. Born Free is the Natural Choice for Safe & Calm Feeding. Natural Milk Flow Baby controls the flow of milk, similar to breastfeeding. Naturally Fuss Free ActiveFlow™ Venting Technology clinically designed to reduce colic and gas. Naturally Safe Free from BPA and PVC. ActiveFlow™ Venting Technology The ideal bottle system for both breastfeeding and formula feeding with a patented, leak-free vent system. Soft Silicone Nipple Available in 5 Flow Rates f.