My RRT-01 2020 feels like it came pre-lubed.
It’s actually the smoothest turning magnetic ring flashlight I own. The ring action is smoother than in my 2012 and 2019 RRT-01, Sunwayman V10A and V11R, and my Jetbeam TCR01.
My new 2020 RRT-01’s ring has absolutely zero grittiness. I also find that I am able to make minute changes to brightness via very small ring movements with no jump. There’s no stickiness in the ring to overcome to get it moving.
FWIW
my RRT01 2019 (with 219B) is ‘somewhat’ linear after you get past the stupid strong on/off detent. There is a slight delay in the ramp on the bottom end still.
my Sunwayman V11R (with LH351D) is more linear at the low end and the upper 25% of the highest end visually appears to do almost nothing.
I suspect there are too many factors to say anything definitive though. If I was BurningPlayd0h I would re-test with a half drained battery and see what changes happen since we know it’s a boost driver.
My RRT01 2020 is in LA customs but i’ll measure CRI and report back when it arrives.
I actually already ran it on a AA Eneloop, and didn’t notice much difference in linearity. Reduced output of course but that seemed proportional across the range of output.
I do like the new RRT-01 and 03. They’re cool lights with a nice interface.
Even though it feels a little odd carrying one around since an FW3A with 18650 installed is the same size as the 18350 Jetbeam, while being much more powerful with much longer battery life.
My 2020 rrt01 has wobbly tail stand regardless if on or off. It looks designed to be flush clicked in but mine missed by about 1/2 mm. It’s a definitely wobbly tail stand.
I asked Jetbeam if it is possible to buy the extension tube separately.
Yes, it is possible. The cost is $10 + $8 shipping
Out of curiosity, I also asked about the hole in the control ring. They stated that it has no function.
That’s funny, they told me it was to put grease in 
At least on the one I just got, it is also perfectly indexed with the back (front?) of the light, so that if the hole is directly opposite the clip, it is at the center of the rotation range.
Mine also won’t do a perfect tail stand, though it is so close when it is clicked on. My initial impression is that I think it is a high cri emitter, just not with the greatest tint. But what do I know, and I haven’t had much time to play with it, maybe tomorrow. Hopefully someone with some equipment can just confirm it one way or the other soon :).
If not already mentioned different copies have different length battery tubes. I have two 2019 versions. One is is clearly longer than the other. The longer one closes all the way and the shorter one has the big gap.
Does the shorter one has strobe and SOS?
> I have two 2019 versions. One is is clearly longer than the other.
that is new info to me
mystery solved
is there a difference in markings to recognize which one is the long model?
hoping someone will do a photo lineup comparing the different variations
Best I can do but the different markings are noticeable. That’s if this picture actually posts!
Crap that didn’t work. Anyone can feel free to post up here. I think all I put up was a link…
No difference in markings on my samples - and a bit less than 3mm difference in length
Engraving looks different.
Engraving looks different.
Not really
The ones that say jetbeamworld.com must be older as it’s not a jetbeam site now. I wonder why they made it longer. Could it be to accommodate protected 18350?
thanks!
a protected 18350 is 4mm longer than unprotected
if the lights were standing on their tails, vertical side by side on a table, the height difference would be more obvious, but I can already see that the difference is revealed by the pocket clip screws… they are in the middle of the tail lug, on the short one and not centered on the long one:
so the threaded portion is unchanged, but the tail end is longer
could you take a photo of the Four Versions of RRT-01, tailstanding side by side?
Sorry about the cat hair, he was sure that I set these up for him to knock down… repeatedly 
thanks for the 4 model photo…
my cat also likes to investigate when I take pics… LOL
your 2012 shares the strobe capable driver with the newer models. (based on no RRT in the serial number itself). These do not fit protected 18350, the light wont close. (I use unprotected IMR 18350, with due diligence)
the short 2019 fits protected 18350, but has a cosmetic gap (does not affect water proofing)
the long 2019 fits protected 18350 with no cosmetic gap
the 2020 fits protected 18350 also with no cosmetic gap