You may be asking yourself "How do I use these?" It's easy!
Soak the pack in water ( 4-5 minutes for the 3 oz, 10-15 minutes for the 8 oz). If you oversaturate the cells, you can squeeze the excess moisture out.
Dry the pack.
Freeze the pack. Make sure you freeze it plastic side down! The fabric side will stick to your freezer, and you're going to have a bad time.
That's all there is to it. The packs can be frozen and reused. You can rehydrate the cells if they start to shrink after multiple uses.