Never thought of chemical warmers as something to rely on -- they're just a luxury alternative to a heating pad. Nice at a Redskins game. I keep some in my car in the winter mostly for acquaintances on winter outings who don't have good gloves.

Experience tracks others -- ones I've had last a couple to a few years past the expiration date.

For reliable warmth I put much more faith in the down booties, mittens/gloves, Smartwool socks/Lowa boots/Gore-Tex gaiters/Marmot pants, sleeping bag, etc. warm and waterproof clothes that I keep in the car fall-winter-early spring.

And matches, firesteel, blah, blah.


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