Head Crown diameter is 26mm (1.024”)
I am a cigar grip addict and since I can't get them for many lights I just wrap lights about 25% up from the tail with a bigger rubberband ..lights i want to use a diffuser on i can add a rubberband on the head of the light and it adds the size i normally need to add one of the bigger Fenix difuser wands.They are a bit bigger than solarforce L2P but with a small rubber band around the head they fit perfectly .
the id is 1 1/2 inch
Wow,I am impressed with how fast this is shipping to me! It made it to New York in 6 days,I live in Suburban Phillly! Should have them Wednesday. 
My other budget light DQG Tiny Triple XPG2 V2 left Seattle on Saturday and is “OUT FOR DELIVERY”!!
Very efficient Richard 8) :bigsmile: and First class mail proves again it is as fast and a lot of times faster than 2 day priority!!
Just got the 18650 “Zoomie”,3 of them……2 worked!
Actually all 3 worked[went on],but One of them had optical problems[was not centered,obstructed and pieces were lose. Then I swear I saw some smoke so I tossed it!! lol!
Not complaining[only a $3.50 light] but mine are far from a “ring free” beam. Once you get to the exterior of the spill there are numerous “Rings of Saturn”.
Maybe you just meant the corona and most of the spill?
got mine today and unfor mine is also full of rings of horror :-). Compared to the Zeusray, the Zeusray is at least 2x as bright w/ a ring-free smooth and wider beam. Compared to the 1-mode SK68 clone with an AA, it was just slightly brighter but those rings… Can’t really complain for the price but the Zeusray is looking like a bargain esp for being a non-modder.
I usually black out everything under the lens .it seems anything reflective around the emitter just causes reflections .I useat leat a black marker and am thinking about reaking out black paint or nail polish . Rings with throw don't matter much in real life usage . if it has rings on flood that s a horse of a different color ... I've de-domed a few xre zoomies lately and the colors are horrible . i've had much better luck with the xpe's tints after de-doming
Edi-t p14
and a favorite edit t-11...... both now have really nasty tints These tints are pretty bad and even de-domed the tint still isn't good ..I need to look and see if maybe these are the fake xpe's ?
Only don’t use tempera colors because after you will have condensation problems, i make this mistake and now i regret it.
I got mine. It is XPE. The focus is surprisingly good as the focus allows for a square hotspot with the die pattern clearly magnified, but there are some rings. It feels cheap and dim.
Cheapest drunk buy ever.
Cheapest drunk buy ever. lol!!!
It feels cheap and dim. Definitely!
Hummm, I gotta warn this is a pretty bad buy. I just got them, only 1/3 work, and that one has such a strongly colored violet-blue beam (yet dim and ringy at the same time) I had to double check and make sure it wasn’t supposed to be a blue LED. The ‘bezel’ seems to be plastic and sharp because its so thin and flakes, but I think it is actually aluminum. O-rings fall off when you unscrew the light to take the battery out.
I got them for “who cares if they are returned” borrowers to use with laptop pulls, but, I think my $1 special buy “police” light that runs on AA is just as good - just about the same amount of light, and less blue.
I just got mine, I don’t see the reason for the light, if it was AA I could give it away.
This light is basically the classic UltraFire ZB-006, listed here at FT (dis-continued): fasttech-ultrafire-zb-006. I mod'ed one a while back, and have another stock one I never got to. Here's my pics from then, showing what I did with the hollow pill:
So, I built a copper pill top, another copper disc inside, de-domed XP-E2 on a SinkPAD, and think I used 2.8A, though not any real gain over a 2.45A. I consider roughly 2.5A to be the top end for a XP-E2. Notice I used a brass adapter ring to mount the driver on. This gave me a little more space inside the pill, maybe limited cells to unprotected - not sure.
I posted about it here: https://budgetlightforum.com/t/-/19751, post #24. At the time I measured 60 kcd, and pretty sure the owner confirmed that #.
I really like this little light though - of course gets real HOT, but super light in the pocket, because there's no metal basically.
Well, yes it is light because of super thin metal (I feel I could probably crush the tube with my hands), but then buy it from Fasttech, not this seller!! 1 out of 3 I bought are working and it has an extremely violet-blue LED, nothing like the Fasttech pics. I think my 18650 battery outweighs the light.
Off to start the claims process 
Good luck with your claim. Do you think it is worth the aggravation for what you paid for them? Maybe just the principle?
You fared worse than I did!! 2 out of 3 worked for me. Those 2 do have a purplish/blue tint to them and as I mentioned before numerous rings of Saturn!
No, its not at all going to be worth the aggravation and time I spend, but yes in principle I want to at least give them some kind of penalty for sending junk and charging people for it. Looking at the Fasttech page Tom E linked these are worse quality even. Right now I’m out $10.50 for trash and one wimpy violet blue inaccurate saturn rings generator, that is annoying… 
Here’re a couple of pics of the one I just got:
The one I got only works with button top batteries, so for some of you whose don’t work, try a button top 18650.
Jim
That’s why you only buy one! And if the quality is good go for more. If my one turns up and is rubbish what have I lost? $4 I could have spent that on a bad coffee from the service station.