New Poundland head torch is actually really neat.

When I saw this I thought it was going to be the usual construction for these things, but it's got a new and novel twist that makes it thinner and lighter than others.

Note that it just provides a wash of light. It's not aimable.

With a set of good alkaline cells (4.5v) the initial current will be:-
High 600mA, low 150mA, flashing 300mA
With a set of nickel metal hydride batteries (3.6V) the current will be:-
High 300mA, low 75mA, flashing 150mA

I'd recommend nickel metal hydride rechargeable cells.
Cheap 300mAh cells will give a run time of 4 hours on the low setting per charge.
Better cells will give a run time of around 10 hours on the low setting per charge.
Light intensity will tail off instead of just going out suddenly as with some lithium powered lights. That avoids being left in the dark unexpectedly.

This would be excellent as a backup light.

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