I grabbed one too since they’re becoming scarce. Thanks Calvin for letting us know. 
I saw a review on the extender that said it was worthless because the light is designed for lithium batteries, and the user was presumably using alkaline batteries. Does an eneloop have the capability to put out at least the advertised 200 lumens?
I am to late
Thanks anyway
Robert
Not sure. Haven’t tested.
Best option for these lights is to grind out the interior of the battery tube. It’s possible to grind it out so that it will fit one the 1100 mAh 18350s.
Should be, if not pretty close. Of course you will get higher output from a CR123 primary, and higher still from an RCR123 (16340) or 14500.
How can you bore for 18350? Does a pic of the 18350 bored tube flashlight exist? I am very skeptical that it can be done, since I put a regular 18650 battery at the mouth of the tube and the fit is just too tight IMHO.
Took my digital caliper out and the V11R tube under the O-ring measures 19.05mm and inside diameter of 17mm so that would leave a half millimeter thick wall…
I think the best bet would be to bore to fit a 17500 battery with the adapter, you would get about the same Mah than the 18350 but just a bit longer light.
I recall reading a posts a few years ago from someone who routinely bored out V10 and V11 tubes using a lathe.
I tried boring out a V11R tube a couple years ago with a cylindrical grinding bit and a hand drill. I didn’t get great results. It works, but I slightly penetrated the sides of the battery tube in the recessed vertical slots between the knurling where there is no lettering. I only penetrated a little bit at the lower corners, but it looked ugly. I ended up super-gluing aluminum strips to cover up the damage.
My technique is so imprecise I didn’t dare try doing it on my camouflage V11R.
No matter, the adapters are gone now. I like the 18350 idea best, but I don’t have the tools for that.
I opened one of the lights I received today, and it is like goshdogit in terms of the low level with an 16340 cell. lower than any other light I have.
Yep, I think this is the best option. Just pick up an extender and bore out the center section. No need to bore out the main tube, as many 17500 cells are less than 17mm in diameter.
The AW 17500s I have are all under 17mm (and 1100mAh).
Might be restocking? If not there are other sources/vendors out there (including directly from the SWM website).
there are other sources, ebay for $15 from China and several other websites that I have not looked closely at prices.
Member mash.m posted that he had bored the V10R in this thread. Sunwayman V10R - Tripple high Cri with battery Monitor
He also boosted the driver to 2 amps. I was hoping he might shed some light on the current increase mystery.
So this worked great. Much lower low now. It goes sub min 
Which part did you file down? The detent or the groove where the detent rides and stops.
On my V10R this worked great also but the magnet holes are not so close to the detent stop.
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For you sub lumen nutz out there, don’t go crazy filing trying to get the low super low.
If you go to far the light goes back to high when the magnets pass the lowest position of the hall effect sensor.
The groove. All the way to the magnet.
I was surprised to see how much current the light draws on the lowest level. 13mA, compared to less than 2mA for my D4. Knowing a bit about electronics its not shocking, the hall effect circuits need to be biased up no matter how much light is being put out.
I was also entertained to see the light level increase a bit when I put my S1R and V11R side by side to compare the brightness on the lowest mode. The V11R gets a bit brighter when the magnet of the S1R is nearby. When the magnet is right near the adjustment ring, the V11R goes to max brightness.
Looks like you slightly got in the magnet pocket.
Looks like that’s about as far as one can go without detent just running into the magnet.
I think it might be possible to gain a little travel from both by filing the dent just a little and the detent groove.
Thanks for sharing Geuzzz 