Posted by: suzanneh on Nov-14-12 10:20 AM (EST)
The instant heat packs that are used for winter sports work well dry but when wet, they lose their ability to work.
This style of hot pack works wet or dry but are not as small as the flat ones.
Nice thing is that they are reusable and you just need to boil them between uses to renew them. (You can NOT microwave them).
There are many brands of these available. Not sure if any one is better than any other. I keep them in my emergency kit.