Perfect for breast milk and formulan88% of moms surveyed in an independent in-home bottle feeding research study said their babies experienced less gas or less spit-up or less fussinessnBreast flow is the only feeding system that requires both suction and compression, just like breast feedingnSoft outer nipple mimics the feel of the breast, allowing babyu0026#39;s tongue to stay in the same position as breastfeedingnPatented inner nipple allows your baby to control the flow naturally like breastfeeding whether you use breast milk or formulanThe Breast flow starter set is perfect for expecting and new moms. The set includes everything needed to get started: two 5 ounce bottles with stage 1 nipples and bottle covers, two 9 ounce bottles with stage 2 flow nipples and bottle covers, a unique snap on bottle container for formula or snacks, and a bottle brush. Breast flow's patented 2 in 1 nipple lets your baby control the flow of breast milk or formula as naturally as breastfeeding. By using both suction and compression motions, your baby is able to regulate the flow of milk unlike any other bottle. Plus, Breast flow is designed to help prevent colic. Moms who participated in an independent in home bottle feeding research study said their babies experienced reduced colic symptoms such as less gas, spit up or fussiness when using Breast flow. Whether you choose to feed your baby breast milk or formula, Breast flow provides a unique bottle feeding experience unlike any other for a satisfied baby and happy mom.