Greetings,
I have come to realize that it's good to have lites that run on different batteries, in case you cannot get the right cells.
For example, if you have one of these new LED Mags but run out of D cells, you can use C cells.
2D Mag will take 3xC cells (Just reverse the spring or put alum foil inside the tailcap)
3D Mag will take 4xC cells
5D Mag should take 6xC cells
I have a Malkoff drop-in module for the Mag, it runs on either 2 or 3 cells. On 2D it runs for about 30 hours but dimmer, on 3C cells you get shorter but brighter runtime.
Furthermore, here is Surefire 9P. The incan module taken out, Malkoff drop in put it (M60LL at 80 lumens)
You get about 12 hours on 3xCR123A primaries at full 80 lumens and much longer but also much dimmer on 2xAA cells. Maybe 20-30 lumens, declining down to 10 lumens.
Note that for AA, you can use any chemistry: L91 Lithium, Alk, NiMH, even Carbon Zinc junk cells.
I got an aftermarket body from FiveMega and it gave me the 3rd option: Li-Ion cells. Here it's pictured with 2x18500 cells. Incredibly diverse light and bulletproof too. Lack of multimodes doesn't bother me.
The really cool thing is, if you have AA as the standard (radio, GPS, lite, et cetera) then you can use 123s for most lumens but be OK with AAs also, for half the lumens but twice the runtime.
Here is another Malkoff product, this one is full power M60 module at 230 lumens. It's configured to run off 1x18650 cells. It's the most readily available Li-Ion cells, usually found in laptops. I run 2900 mAh Panasonics for incredible runtime (1.5 hours of full lumens and then 2 hours of tail lite as it drops out of regulation)
The really cool thing here is you can also use 2xCR123A cells. I usually have a Li-Ion in it but for backups, use primaries. You should be able to always find something for it.
This one is another aftermarket body by Leef, designed to use either 4xCR123 primary cells or 2x18650 Li-Ion. I would think it can also run on 2x18500 plus a spacer cell. It has a custom made Malkoff module that runs on 5V-12V. Very nice lite, great runtime for serious TSHTF time.
Now who said Surefire cannot run on AA cells?
Here is a custom made body by FiveMega, to take 3xAA cells and a P60 drop-in. It has another Malkoff, M30 in it.
(On the left)
The 3xAA Malkoff M30 will run on any AA chemistry: Energ Lithium (L91), NiMh, Alkaline, old style "heavy duty" garbage cells. The output will vary from strongest to weakest. For serious TSHTF get lithiums but it will run for hours even on non-Lithiums, at reduced lumens. In all honestly Alks quickly get dim but once they get dim they still run forever. I was really shocked when Zinc Carbon cells "Eveready 'heavy duty'" cells worked in it. Another strong candidate for TSHTF lite.
Disadvantage: Tailcap is non-standard.
Here are all 4 of them:
The really cool thing is that modules can be shuffled around, for example M30 can be put in 6P clone to get more lumens but shorter runtime. Or M60LL can be put in the 2x18650 lite for greater runtime. Start messing with Surefire (Or SF clones) Legos and there is a good chance you might end up with a configuration nobody else has.
I have come to realize that it's good to have lites that run on different batteries, in case you cannot get the right cells.
For example, if you have one of these new LED Mags but run out of D cells, you can use C cells.
2D Mag will take 3xC cells (Just reverse the spring or put alum foil inside the tailcap)
3D Mag will take 4xC cells
5D Mag should take 6xC cells
I have a Malkoff drop-in module for the Mag, it runs on either 2 or 3 cells. On 2D it runs for about 30 hours but dimmer, on 3C cells you get shorter but brighter runtime.
Furthermore, here is Surefire 9P. The incan module taken out, Malkoff drop in put it (M60LL at 80 lumens)
You get about 12 hours on 3xCR123A primaries at full 80 lumens and much longer but also much dimmer on 2xAA cells. Maybe 20-30 lumens, declining down to 10 lumens.
Note that for AA, you can use any chemistry: L91 Lithium, Alk, NiMH, even Carbon Zinc junk cells.
I got an aftermarket body from FiveMega and it gave me the 3rd option: Li-Ion cells. Here it's pictured with 2x18500 cells. Incredibly diverse light and bulletproof too. Lack of multimodes doesn't bother me.
The really cool thing is, if you have AA as the standard (radio, GPS, lite, et cetera) then you can use 123s for most lumens but be OK with AAs also, for half the lumens but twice the runtime.

Here is another Malkoff product, this one is full power M60 module at 230 lumens. It's configured to run off 1x18650 cells. It's the most readily available Li-Ion cells, usually found in laptops. I run 2900 mAh Panasonics for incredible runtime (1.5 hours of full lumens and then 2 hours of tail lite as it drops out of regulation)
The really cool thing here is you can also use 2xCR123A cells. I usually have a Li-Ion in it but for backups, use primaries. You should be able to always find something for it.


This one is another aftermarket body by Leef, designed to use either 4xCR123 primary cells or 2x18650 Li-Ion. I would think it can also run on 2x18500 plus a spacer cell. It has a custom made Malkoff module that runs on 5V-12V. Very nice lite, great runtime for serious TSHTF time.

Now who said Surefire cannot run on AA cells?
Here is a custom made body by FiveMega, to take 3xAA cells and a P60 drop-in. It has another Malkoff, M30 in it.
(On the left)

The 3xAA Malkoff M30 will run on any AA chemistry: Energ Lithium (L91), NiMh, Alkaline, old style "heavy duty" garbage cells. The output will vary from strongest to weakest. For serious TSHTF get lithiums but it will run for hours even on non-Lithiums, at reduced lumens. In all honestly Alks quickly get dim but once they get dim they still run forever. I was really shocked when Zinc Carbon cells "Eveready 'heavy duty'" cells worked in it. Another strong candidate for TSHTF lite.
Disadvantage: Tailcap is non-standard.
Here are all 4 of them:

The really cool thing is that modules can be shuffled around, for example M30 can be put in 6P clone to get more lumens but shorter runtime. Or M60LL can be put in the 2x18650 lite for greater runtime. Start messing with Surefire (Or SF clones) Legos and there is a good chance you might end up with a configuration nobody else has.