"LED Lights / Heads compatible with 3.6 volt rechargeable batteries:
* NovaTac EDC series flashlights
* Fenix brand flashlights
* Lighthound Cree drop-in
Incandescent Lights / Heads compatible with two 3.6 volt rechargeable batteries:
* Lumens Factory Bulbs
* Chinese Flashlights, ONLY WITH 8 Volt bulb.
LED Lights / Heads NOT compatible with 3.6 volt rechargeable batteries:
* All SureFire® Flashlights
* All Inova Flashlights
* All Nuwai Flashlights
* All Streamlight Flashlights
Incandescent Lights / Heads NOT compatible with 3.6 volt rechargeable batteries:
* Most Incandescent bulbs are NOT compatible. We only recommend the Lumens Factory bulbs for use with rechargeable batteries"
This comes from LIGHTHOUND.COM. Here is the link:
http://www.lighthound.com/index.asp?PageAction=Custom&ID=4
Mark