I was just going through my car kit, and re-discovered some old Coghlan's hand warmers I had stashed in a tub. These were about 4 years old now, and I know these things have a limited shelf life.

I took them out, and they felt a little "stiff", so I opened one up to test it out.. but I guess they were just packed really tightly.

I took it out, shook it up, felt to see if there were any "clumps", and sure enough, I could feel it start to warm right up.

Guess I'll throw them into my backpack and get them used up the next time I'm in a situation that I need them. But I was rather impressed with the lifespan of these.

Other's were good for maybe a year...