A couple of years ago, I accidentally fried the driver on my Tank007 TK-703 following a poorly-implemented modding attempt. I was unable to find an appropriate driver so I wired the light to run Direct-Drive until I purchased my Tank007 E09 which became my new EDC. Several weeks ago, I purchased an assortment of drivers from DX, including SKU.128084; a "350~400mA Regulated LED Driver Circuit Board for DIY Flashlight (1.2~1.5V)". It's one of the very few 12mm drivers I was able to find. I successfully installed the driver which was a perfect fit for the TK-703. The light functioned perfectly, but at reduced brightness, from an Alkaline AAA cell. As the driver is sold in pairs, leaving me a spare in case I fried one, I dropped a 10440 into the light and the light continued to work normally and at full brightness from the Li-Ion cell. I have been carrying this light as an EDC for about a week since I installed the new driver, and it continues to work properly on both Alkaline and Li-Ions. I assume it's running direct-drive from the 10440s, but at least it works now...
I'm very happy to have this light back in service, as it has an excellent aluminum SMO reflector combined with an EZ-900-die XR-E emitter making this an extremely throwy light for such a compact single-AAA-sized light. It has a very well focused and bright hotspot. My biggest gripes with this light are the lack of the tailcap spring requiring it to be modded to allow the use of 10440s in the first place, and that it is too short to take Protected 10440s. I purchased a pair of protected UltraFire 10440s to use in my E09 but they wouldn't fit it; now they won't fit this light either, so they still sit unused.
Tank007 TK-703 - $15.50 - Kind of pricy by modern AAA/keychain light standards: http://www.manafont.com/product_info.php/tank007-tk703-haiii-7090xre-120lumen-led-flashlight-black-1aaa110440-p-4423
driver - http://dx.com/p/350-400ma-regulated-led-driver-circuit-board-for-diy-flashlight-1-2-1-5v-128084
