This was the most useful thing I owned during my time in NICU. It is made entirely of collapsable ice packs made of gel and folds up like an envelope when empty. It's perfect for transporting milk especially during long commutes, summer, or if you have to make a stop before the hospital. It is the perfect cooler, in my opinion, because once you've given the nurse your bottles you can just fold it up and put it in your babybag (or purse!) and it's out of everyones way. They frequently said they wished everyone had one. I liked the robots, but they come in many patterns and colors.