Quote kzb:
Possibly I could get it to work with a ring of copper wire or paperclip made into a ring to fit between the battery tube and the tailcap contact. Or ideally a copper or brass washer of the right size, if I could find one, I guess.
Now you got it… :+1:
I didn’t buy it for a bodgit job though. I’m disappointed, but then I thought it was too good to be true at the price.
If they’d made the tube just 0.5mm longer it would probably work with Xtars.
If it works with the paperclip bodge, I might try for a better bodge by obtaining a copper washer of the appropriate dimensions.
I never use protected in a single AA/14500 setup. And I really don’t see a need to. So, problem solved. I knew I’d use non-protected before I even ordered UT01. Simple.
YMMV 
I cut a length of cable long enough to make a ring within the tailcap. Stripped off the insulation, twisted it a bit to keep the fibres in place and put it in the tailcap so that it makes contact with the battery tube end.
Result ! The flashlight does indeed function with Xtar 14500 cell with this bodge in place. The copper stays wedged in place also.
Anyhow I hope this is useful information for others considering buying this.
It seems all protected cells, *including those purporting to be “AA-sized*” are too long and won’t work in this flashlight. Unless anyone knows of a shorter cell than the Xtar of course.
It is verry hard to find a PROTECTED LiIon 14500. They are normaly longer than the nominal 50mm.
Xstar are short with arround 51mm others more on the 52mm side.
Are these definitely Protected? It’s not clear from the FastTech site. In fact there is another Sanyo cell advertised, “Sold Out”, that is 50mm. Maybe that is the protected version, and how do we know the 50mm is not “nominal”?
I don’t think those are protected.
Reading the comments on the FastTech, I also think they are not protected.
Nominal:
14500 = are the dimension of a cell in milimeter 14 = 14mm diameter, 50 = 50mm long, End Zero = indicate its a round cell.
Same logic with a coin cell CR3230 : Round cell 32mm diameter, 3mm hight.
Here’s what i did to make it fit protected 14500:
…but it’s a lot of work i guess…
Copper sealing washers available on ebay; 18mm OD, 14mm ID, 1.5mm thick. Would this be a good idea?
I am concerned about contact resistance, especially since there is quite a high current.
I am also wondering if the added resistance is limiting the performance. It does not seem any brighter than my Lumintop ED11 560 lumens.
You MAY find that the protected variety of cells are not completely capable of putting out max amps that the driver needs for DD turbo. That’s why they call them protected. It’s possible for their circuitry to prevent max amp flow.
I use the 14500 unprotected IMR WindyFire’s. Man, the UT01 is really scorching bright with that.
Again, YMMV with protected cells.
Replace the faulty switch( yes, i lost the lotery, poor me 
)
Nearly 10$ include shipping just for 5 switches