Zippo Hand Warmer review
It may not be the usual form of technology we review, but this hand warmer is a clever gadget that'll keep you warm this winter. Unlike the chemical versions, this runs on lighter fluid: you simply fill it up using the included plastic jug.
The initial fill uses a lot of fuel to soak the cotton-wool like filling, but once done, it uses very little to remain hot for hours. A full tank should last 12 hours, but you can fill it up less if you don't need that long. The Hand Warmer burns with no flame thanks to a platinum catalysed glass fibre burner, although it does give off a faint lighter fluid odour.
Impressively, it remained hot in our tests for exactly the claimed time and, at 45 degrees C, was miles hotter than other hand warmers we've tried. The metal is too hot to touch, of course, but inside the included pouch it's just about perfect.
It isn't the cheapest hand warmer, but it's certainly the hottest and most convenient.