Saw something like these watching the new Russian bushcraft show. Looking through the related forums, I had realized that they've became very popular among Russian "bush-men" in recent years. Probably because of their nearly infinite reusability.


The principle is simple. The pack generates heat when the salt inside starts to crystallize after initiation by the catalytic element inside. To recharge - just boil it until completely soft again.

Does anyone have any experience with the above product available on the US market? Can it be good for camping? Or perhaps there are other similar heaters available?

There was a company marketing a similar handwarmer several years ago. In theory, its not a bad idea. Having to boil it to recharge it is a serious fail for me. Over the years, I've tried several different handwarmer options over the years. The air activated kind work well. The charcoal stick type, at least for me, tend to burn for a few minutes and go out. I've got one of the Zippo Catalyst types to try this winter.

I got one a few years ago. They work, and they're fun to play with - I actually quite liked the idea of boiling to recharge - I hate nonresuable things where it costs you a buck or two just to try it out. But they are rather heavy; they contain a fluid so it's like lugging around a small hot water bottle. I wouldn't carry it camping or hiking, but it's fine to keep around the house. It's exactly the heat equivalent of those packs you keep in the freezer - good for first aid, but still kind of heavy and one-shot-use for travelling with.

I have used several of these-


Plusses
reusable
cheap


minuses
EASY TO BREAK- I try to be careful, but the plastic does not seem to last all that long- most of mine broke/leaked within a month.

Short they only release heat for 30-45 minutes. Enough to shovel, but not that long

storage They do not STAY liquid; whether mine just get bumped in storage, or they somehow age; I I left it and came back a few months later, they were all crystallized, and had to be heated to use-

Bad QC- when I bought them, I would buy 3 or 4 at a time- they never maintained temp the same between each batch-

I'm not sure I understand. After boiling it starts generating heat immediately? If so, it seems like it wouldn't be much more useful than a hot water bottle. I guess it is an exothermic reaction which would presumably put out more heat than a hot water bottle.

But you can't get heat on demand later as with other hand-warmers.

I still use one of those metal hand-warmers that use lighter fluid that I have had for about 40 years.

That tech has been around for over 20 years. Never seemed to get beyond the problems Cranston listed. Not worth the weight or hassle to me.

No- There is a little disc inside that you have to flex to start the reaction; it does not start immediately.

if i leave them for a few weeks< no problem> if i check in a few months, Most of them are crystallized- not sure if a time issue or a kid issue.... lol. In either case, the plastic melts, the plastic leaks.. nice gimmick, not read for real time....

Here's a fun way to re-purpose the ones that start leaking.
http://www.youtube.com/watch?v=D1PDE5OawuI

Very helpful review, LCranston, thanks. It looks like these are not marketed for camping for a reason - not sturdy enough for a typical field abuse.

For the problems mentioned above:

• the Russian model seems to be better as it is able to generate heat for 2-4 hours (when used under clothing and in the sleeping bag).
• The plastic on those looks beige instead of blue, and holds well at -20 C (-4F)
• The noted spontaneous crystallization after prolonged storage time is typical for any saturated solution of salts. To prevent that you have to shake the solution periodically.

It looks like somewhat different brands to me.
Anyway, just ordered one for testing and in hope to improve some of its properties, because infinite reusability is really very appealing to me. Going to try ordering the Russian model to compare.