My D1 fit the D4 short tube with no issue, but a friend of mine just got the D1 with a spare short tube and it doesn’t work with the D1. I haven’t seen it, so I don’t know exactly what the issue is but he tells me it only screws in part way.
Dale
I’m relatively new here, how does one start a thread on this forum?
On the left, go to Forum Categories, find the category that best suits what you want to post, and start a thread. 
I’m old here and still screw it up. 
I’m hoping to see some manufacturers bore their flashlights for 20700 cells and supply a sleeve for 18650 cells. The spring length might pose a problem though. Still, it would be nice to know that if and when 20700 cells start to make headway and are available, lights would be able to use them and the old standby 18650 cells will still work in a pinch.
Is this do-able or am I missing something?
It is pretty doable. A lots of flashlight compatible with unprotected and protected batteries so they capable to run cells from 65 to 70mm in length.
it does not reach a stable balance, the brightness varies continuously
this is what the thermal fluctuations look like, starting at 1000 lumens, per CRX data… search this thread for his posts with more details
Here’s that table
I’d ask which is spicier — the light or the pepper plant — but I know better. That’s a very spicy pepper.
In more detail, the output should look more like this:
But the behavior varies with the emitter type, user-configured temperature limit, environmental conditions, battery type, etc. Output isn’t as stable as I’d like, but it should generally at least avoid damaging itself or the person holding it.
Got my Blue D4 in:
The surface is much rougher than the old green. The old green is honestly my best feeling light, it just feels nice and smooth in the hand. The new one is a little rough on the hands at first, but I think it will be better after several days in a pocket. Frosted optic with the 219C is amazing. I could definitely use this with my head strap now to illuminate my path evenly instead of a narrow circle. Will hopefully make a nice photography light when exploring. I had to clean up the threads a bit because the anodizing made them gritty which wasn’t a problem in my green one which was smooth on arrival. All is well now though. For people that thought the initial D4 was too smooth, the new anodizing definitely lets you get more purchase on it.
It’d work if there is enough wall thickness….You’re taking 1mm off each side… so the wall thickness should be at least double that….but a 1mm resulting wall thickness, will that be strong enough?
The coating on my cyan is fantastic. No one is pulling it from my grip. I wish I had that coating on my back stairs before I fell
I didn’t realize I had to purchase tracking on the cyan D4, so I’m in the dark on where it is. I’ve got less than a month, should be here, but I’m getting nervous… lol
Yeah my cyan didn’t have shipping by default like my first green one did. It took about 3 weeks to come in.
My blue D4 arrived today,a new shipping record 10 days to Australia,got to get lucky sometimes I suppose.
I think if your order is less than 80$ and you don’t purchase tracking nr , your order gets canceled . Take a look at it
If your order is less than $20, you need to purchase a tracking # for $2 or the order will be canceled.
If the order is less than $80, you have the option to purchase tracking for $2.
Over $80, tracking is included.
My wife’s favorite color is blue, so this is for her birthday next month. Surely it’ll make it in time, but just because I need it to there’s every chance it won’t, ya know? lol I even considered putting blue XP-E2’s in it, to blue it out like I greened out my green D4. 
I could be wrong here, but… I get the feeling you are never in the dark.
My quad of quads. Cyan and Green are nichia. Black is xp-g2 s4 5d, Grey is xp-g2 s4 3d. Last picture is how they fit in the Jetbeam mini holster.
