This portable battery pack and power supply is the perfect addition to your Medela electric breast pump. With the convenience of battery operation, you can take your pump with you wherever you go without needing access to an electrical outlet. The black color and model number 901.7002 ensure that you are purchasing a genuine Medela product. The battery pack is designed to fit your specific Medela breast pump model and is easy to use. Simply insert 8 AAA batteries and connect the power supply to the pump. This is a must-have accessory for busy moms on-the-go who want the flexibility to pump whenever and wherever they need to.