We bought this set of 8 reusable ice packs for use in our 6-can cooler. They measure 5x7x.5 inches each and I can't tell but they seem to be filled with a thick blue liquid. They freeze well and work fine for our purpose. Because they are thin, they thaw faster than I would have liked, but they work fine for our use. You can double them up to last longer. Make sure your cans are well-chilled before putting them in the cooler. Still, for a buck each, they are a bargain.