Forgive if this is a wrong questions. But I have a plan to build variable output on my SF L4 using a McClicky tailcap. Is it possible to use Flupic in it. Or any other alternatives to this build? Cheers.
Sorry, the FLuPIC was not designed for use in 6 volt flashlights.
It's better suited powering the 3.0~4.0 forward voltage leds like the Lux1, Lux3, and Cree XR-E from a single rechargable li-ion cell.
Goldserve could help you more, but you can use a FLuPic with a McClickie switch if you only use one cell like a 17670. You will probably need to change the LED to a LuxIII to get the Vf down below 5v. There are some great modders on here that do wonders with KL4 heads.