Would either Sofirn or Wurkkos short tubes fit to shorten the SF16-UV and use the 18350 batteries?
If the answer is ‘yes’, as I hope, is there any practical difference between those 18350 tubes? Do they have the same thread?
Please, could somebody with the SF16 (@Lightbringer?) check if the short-tube mod is possible at all… 
I would… if I had one. Or even if I did, if I’d even know where it is.
But weren’t different versions threaded differently?
2 Thanks
Awesome!
But weren’t some different shape threads, like triangular vs square or somesuch, even though they were the same pitch?
All I vaguely vaguely vaguely remember is that some people were grexing that new vs old were different threads and no longer interchangeable, 'though I’m not sure at all what brand(s). Might’ve even been Convoy S2+ tubes, no idea.
From convoylight.com:
18350 battery tube with rectangular thread is also suitable for S3 and S6 flashlight(Latest version).
18350 battery tube for S2+ flashlight
The trapezoidal thread on each end of the 18350 tube has 5 turns. If it is a rectangular thread, it has 4 turns.
The trapezoidal thread is used for the old version of S2+, and the rectangular thread is used for the new version of S2+. Buyers should pay attention to the distinction.
Ah, that’s gotta be it, then.