Its the perfect companion for mothers who already own a Medela breast pump compatible with the classic bottle set and want to be able to express milk hands-free, without having to buy a new pump. It can also be purchased as an additional set for owners of Medela hands-free pumps. Composition Anatomical design: The hands-free collection cups are designed to anatomically fit most breast shapes and nursing bras and feature research-based Medela technologies, such as the 105-degree angled funnel. Lightweight and comfortable: Our portable cups are among the lightest on the market. Designed to avoid overloading the breasts, they maintain the natural shape of the breasts, making them discreet under clothing. Easy cleaning: Makes your life easier with only 3 parts to clean and easy assembly. Its dishwasher safe and easy to use, both before and after removal.