BIG Leef System - as described here:
Big Leef System post on CPF - edited version also copied below.
CONSTRUCTION The body was machined on a CNC lathe from 6061 heat treated aluminum alloy, then hard anodized.
LUBRICATION Please do not assemble this body to any part without some lubrication on the threads. Galling can occur on completely un-lubricated threads.
To review, the BigLeef is a multi-battery, modular system consisting of a neck, one or more bodies, and a tailcap. There are necks for the SF M-series and C-series heads and the M*g D head. Behind that, one or more bodies can be screwed together for one or multiple cell capacity. The bodies fit together closely and overlap for nearly an inch, so the joint is quite strong. Finally, the tailcap screws into the body and has a tactical clicky switch that will handle most hotwire current loads (a higher capacity switch will be offered, but it'll be a reverse clicky). All joints are sealed with an o-ring.
The BigLeef has two different body sizes. One is for the protected, rechargeable LiIon cell offered by AW, having a capacity of 3,300 mAh (50% greater than the 18650). These bodies also fit NiMh and other standard size C cells.
The second body fits the ~26670 Moli Li-Ion cells and the new A123 26650 cell. These are used by Milwaukee and DeWalt in their power tools and have three advantages: they're safe, and they can be discharged and charged at rates unheard of in the flashlight world (30 C continuous discharge and <5 min. full charge). See www.a123systems.com for more information on the A123 cells. Milkyspit has built lights around this cell -- keep an eye on his pages.
There are other Leef parts that might become a part of the BigLeef system, for example the soon-to-be-announced LeefHeads . My interest in developing such things depends on the success of the basic unit.
As has always been the case, I sincerely appreciate your interest in all Leef parts. Let the games begin!