I was just looking around in my local outdoor-shop. Trere I saw a bag filled with blue gel and a little metal plate inside. The brand was Vaude (German). I asked it to the sailsman and he told me it was a heat pack.
If you snap the metal plate, the gel would become solid and warm up to a temperature of 55 Celcius. After about an hour, it gets cold , but if you boil it in water, it becomes liquid again.
It's reusable for about 100 times.
I got one for free from him. Regular costumer you know...
Has anyone of you used these before? Are they a good replacement for chemical heat packs?
Let me know.
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