Partners Brand PIBB6 Ice-Brix Packs, 6 oz., 5 1/2" x 4" x 3/4", White (Pack of 96)

These things freeze fast. They freeze hard and cold, colder than ice (as they say on the packet). They can fit in small spaces, between larger things, so you can really pack a container with these things, much more so than bulky ice packs.They don't pile up or stack very well, so you either want to keep the stacks small, like 5 or 6 of them, or you want to put them between other things, or you want to put them in a container. I freeze mine in a plastic bin in the freezer. I have another bin in the fridge ready to go to the freezer when the first ones come out.I don't abuse these packets, but my uses are somewhat rough, and I've only had one puncture. I repaired mine with a little epoxy, which worked great, but given that you get a big box full of these things, losing one in a blue moon might not be a big deal. They're non-toxic, so a puncture will not poison nearby food.The only downside isn't really a downside. They freeze fast, yes, but they also melt fast. That's because they rapidly transmit their coldness to the things next to them; they cool things down quickly. In a small container like a lunch box, I don't think this is a problem; they'll hold fine until lunch. For larger areas or water that you want to cool, my solution is to combine them with larger freezer packs that cool more slowly. Then you get the best of both worlds. And of course you don't have to clean up any water when they melt, at least not water from these packs; you can easily just remove them and put them in a bag somewhere to re-freeze later. I do recommend freezing them dry; I think the one I punctured did so because it froze in wet form next to another packet. And speaking of wetness and dryness, it's no problem hand-washing these under a faucet. I would not put them in a dishwasher.Did I mention they're pretty inexpensive? Compared to more "high end" freezer pack products that don't really work better, they're downright cheap.