Now I'm one of those poor souls whose hands and feet remain freezing cold from October to late May every year, so I thought maybe one of these nifty little hand-warmers might be useful.
After taking stock of the reviews currently on amazon, I took a punt and ordered one as it wasn't a huge amount of money.
It arrived very quickly indeed, and I tried the warmer over the weekend.
The charcoal lit very easily - you just need to make sure you hold the lighting flame on the end of the charcoal stick for long enough to see the red glow right through to the middle of the stick. Might take a couple of minutes of lighting and gentle blowing to be sure; just like trying to light a charcoal disc to put incense on, it isn't lit enough if just the very edge is only just alight. I gave it a couple of gentle blows just to be sure, and shut the lid.
From a gentle warmth initially, it gradually built up over 2 to 3 hours, and provided a lovely relief from cold hands. After this time, it became proper hot and needed to be put into the secondary pouch. This real heat then lasted for a further 2 hours, making the heat from one charcoal stick last at least 5 hours. Super.
When the instructions say to beware of real heat from this, they do mean it; it just takes time to build up.
And the end result of the ash from the burnt charcoal was easily disposed of - just open the burner up and tip it out (when cold!) into a bin. Leaves a clean pad on which to place the next stick to be burned. Sorted.
It does smell of burning charcoal, and if you sniff at your hands, there is that smell there for sure, but after all, that's what it's doing to provide you with the heat. But it's only a really strong smell if you sniff at the casing, and I find that a small price to pay for warm hands. I probably wouldn't notice it in the middle of a camping field where there are fires lit around about.
I like this, it's a fab idea, and it works. And I'm very much looking forward to having warm hands on cold camping trips.