My personal opinion to follow:
1. buy the 11836 as others have suggested.
2. Buy an AW brand 17670 (or 2, if you want a spare) and a charger for it/them (DSD, WF-139, Pila IBC if you are willing.)
3. If you want to, you could pick up an aluminum bezel for it, but it's not totally necessary with this setup and here's why:
The 11836 uses a buck regulation circuit that needs 4.5V or more (haven't determined exact V requirement for regulation but it is at least 4.5V or higher) to run in full regulation. Below that, the module operates at a much more conservative drive level and produces a lot less heat.
Here are some of my observations:
In a brinkman Maxfire on an 18650 (I bored it), the 11836 starts off around 0.5A draw. That's less than 2 watts of power consumption. The module is still very respectably bright at this drive level. Since it is being driven less hard, it will not get as hot. I ran it for ~5-10 minutes straight the other day, pulled the module out to feel how hot it was, and it was only warm to the touch.
Since it will be basically direct driving the LED with some voltage drop from the regulator, the power consumption will drop as the battery depletes, this will further reduce the amount of heat generated by the module as it runs.
I don't normally recommend configurations like this with non-regulated diminishing output through the run. But in the case of Polomer body lights, you are confronted with a few options and obstacles....
1. A malkoff low output module will work with regulation on 2xRCR123s, or with diminishing output on 1x17670, but is probably more than you want to spend on a gift, and it's worth more than the G2 it's going into.
2. A SureFire P60L will work, as it's thermally regulated, but it's not the most efficient option as it's still using the original Seoul P4. Not very impressive output for the power consumption. This one will work on either 2xRCR123s or 17670s, operating below regulated level on a 17670. Again, this option costs more than the G2 it is going into.
3. A multi-mode LED module, combined with a user who understands and respects the thermal limitations of the module and self imposes runtime restrictions on using the higher modes to prevent overheating. (not practical for a gift or non-flashaholic).
4. A buck regulated single mode module that runs at a nice conservative diminishing level on 1x17670. This is the cheapest and most practical option for a gifted module intended for a polymer bodied light. The output of the 11836 on a 17670 still beats the P60L on 2xRCR123s, and it runs at similar or less power.
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This concept has inspired me to do some further testing on the 11836 on an 18650 (in your case, it will be a 17670, but the 18650 will theoretically push it slightly harder and hold the output up longer)...
I'm going to get out a temp gage and run this thing from a fresh cell for a good while and test the temperature and power draw periodically. I'll report my findings in this thread.
Eric
. The Aluminum bodied lights need to be bored out, and I dont think its possible to do that with the G2.
The Surefire P60L has a build temperature control that will reduce the led output, to keep it from burning itself, most other P60 clones does not have this temperature control!
