Born Free Classic Bottles are designed to meet the feeding needs of all babies. The patented ActiveFlow venting technology allows baby to control milk flow for the most natural feeding experience, making it easier to switch between bottle and breast. Clinically designed to reduce colic and gas, BPA-free Born Free bottles are the natural choice for safe and calm feeding. Natural milk flow for an experience similar to breastfeeding, allows baby to control the flow and helps prevent nipple confusion Naturally fuss free, clinically designed to reduce colic and gas with the leak-free ActiveFlow venting technology; preferred by moms with colicky babies Naturally safe, durable bottles are free from BPA and PVC Nipples, collars, valves, and sippy cup spouts and handles are interchangeable on all Born Free bottles and transition cups Includes Level 1 (slow flow) soft silicone nipple.