Evenflo's Advanced Single Electric Breast Pump is designed with our PerfectlyPure™ closed system, which prevents milk backup and provides easy cleaning. This breast pump includes 2 flange sizes and is compatible with Evenflo's AdvancedFit™ flange system, which has 6 different sizes available. Enjoy slouch-free pumping with our PerfectPosition™ flange angle, and easy fingertip control for quick on/off and customizable vacuum. Super compact, lightweight, one-hand design is perfect for pumping on the go or a night out away from baby. The Advanced Single Electric Pump can be powered by the provided AC adapter or 3 AA brand name batteries (batteries sold separately). Plus, this breast pump works with the Evenflo Advanced Milk Storage Bag Adapters, allowing you to store milk faster and reduce milk loss when transferring from collection bottle to storage bag.It is Evenflo’s goal to not only provide mom with dependable, quality products, but also ensure she has the resources she needs to have a positive and successful breastfeeding and pumping experience. To reach this goal, Evenflo is excited to include comprehensive breastfeeding education with the purchase of your pump. Developed by our partner, Breastfeeding Expert Shari Criso (IBCLC, CNM, RN), Simply Breastfeeding™ is a practical and proven program that has helped thousands of moms successfully breastfeed.We are honored to support you on your breastfeeding journey. For over 30 years, Evenflo has created and continues to develop products to help you along the way. Good luck to you as you continue on your amazing adventure of parenthood!