Similac SimplySmart, designed by experts in infant nutrition. Made in partnership with moms, it has the smart features you want. Features including smart close which lock out leaks and Intellivent a venting system designed to reduce baby"s excess air intake for less fussiness and gas. A variety of nipple flow rates made exclusively for this bottle system are also available to fit your baby"s feeding needs. Contains two 8 oz bottles, Two 4 oz bottles, 4 level 1 nipples, 1 Similac On-the-Go powder.