I bought this to hold my breast pump, parts, and milk all in one container for my return to work after having a baby.  I have a Medela Pump in Style setup, and I'm able to fit everything I need for the day inside.  Most importantly, this helps to keep my ice pack and breast milk cool during the day.  I haven't challenged it with more than this yet, but I can at least say that it's a great size and style for daily use and maintains the cool temp I need.