I am a bag junkie (un-diagnosed) and this bag if absolutely wonderful. I have the Elvie mobile pumps, so I store them on the one side and put the cooler bag on the other side, the big compartment I used for a bottle, spare clothes for the kiddos, my laptop, planner, wallet. LOVE the key attach thingy. When I don't carry my pump around I push the sides out (or in?) and snap them shut, the bag can house so much stuff, yet it's not bulky. Absolutely in love and will recommend to every new momma I see.