Not going to happen.....
a green laser module is about the same length of two CR123 batteries....
true, you may get it to fit inside the flashlight.......if you remove the battery.
If you absolutely want one in a flashlight host, Look for a flashlight that either takes 2xCR2,CR123 or AA
basicly what will happen is by the time you get the module into the flashlight, there will prob be just enough room to get one battery in.
for example, the Coleman max flashlight that is sold at wal-mart that takes 2xCR2 batteries, will perfectly fit one CR2 battery once you get the module in.
and i believe flaminpyro is selling heatsink for them...so theres on option for you.
host= $25
heatsink from pyro = $25
green Module = ??
what kind of budget are you on anyways?
Ehgemus sells hosts made for green modules over in the buy sell trade section.