M21B does not fit, so I assume the rest also will not fit.
Also mine came with reflector rattling. Solved in a minute of course
This lantern has a different bezel mount design. The sealing ring does not rest against the reflector, but against the lamp housing around the perimeter. When tightened, the bezel first pushes the rubber band, and only at the end presses the reflector. As other participants in the discussion have already written above, when tightening, you need to press firmly with your palm.
Hope my “lame” english can be understood ).
I figured out how, when turned on, it is guaranteed to get into the first low mode. If you turn it on by pressing 6 times, then the control mode is changed with the inclusion of the minimum mode. The crutch is certainly uncomfortable, but it’s better than getting an unexpected turbo mode.
For some reason, the following began to happen with my flashlight: when switching from a stepped mode to a smooth ramping mode, in the first few seconds the flashlight spontaneously raises its brightness by three small steps, up to about 90lm.
I added 3 more beamshots of stepped ramping mode in the Beamshots section.
And it’s worth mentioning I edited the review after some time and added info about simple 4 mode UI available after 6 clicks. Sorry I didn’t mention it earlier, and I gave this flashlight worse rating than I should. I changed that too.
I put orange peel reflector on my lantern. As expected, the transition from hotspot to side illumination became smooth, the light became more convenient at close range. At the same time, I did not notice the loss of range.
I have an M21C U and also a M21C and M26C. What annoys me is the gap between the bezel and the body. My bezels also came not fully tightened. On the M21C U there were a couple of small burrs in the threads which I scraped then lubed the bezel and forced it past the burrs so it is as tight as possible but still has a small (maybe .25 mm) gap as do the other two lights. If you look from the side you can see daylight between the bezel and the body. Seems something is out of spec, likely the bezels. It bothers me as as the lights seem perfect otherwise. (except for the ramping issue on M21C U), and my other lights with the same type bezel (non Convoy) are all fine.
Can anyone confirm if this light uses the regular C8/C8+/M21A reflector?
I have C8+ but this reflector (M21C) is bigger
Alright thanks. I’m thinking of getting this light and swapping in a Linings SST-70. I have had very good results with that LED in my Convoy L6. Pure white, no ugly corona, good throw. Such an underrated LED!
Maybe a stupid question but how can I insert the orange peel reflector? Do I have to remove the silver ring on the head? If yes how?
Hello.
You’re right, you need to unscrew the stainless steel pressure ring located on top.
Can be unscrewed by hand counterclockwise while pressing the ring with palm. When reassembling (twisting clockwise), you need to firmly press the ring with your palm in order to firmly press the sealing rubber ring located between the silver ring and the flashlight body. Otherwise, if it is not tightly screwed, the glass may rattle.
Another question. After receiving my M21C-U it did not work. I contacted Convoy and they send me a new spring. After replacing the spring the flashlight works. But with 100% it steps back after roughly 5 seconds to low mode. What can cause this?
My new spring looks like this:
On other reviews I saw that the spring looks like here:
Why there are three different versions of springs and how can I solve my problem?
An additional wire (shunt) is placed when the spring cannot conduct the required current through itself. The shunt-free version has a spring with better electrical conductivity, Simon says. You may have a lowcurrent battery. For turbo mode, a battery with a constant current output of at least 10A is needed.
Thanks for the explanation. I tested two different Samsung INR21700-40T which work perfectly fine in other flashlights. That’s why I think the spring can cause this.
Funny, I PM’d Simon and told him about the rattling bezel in my M26 and M21 and he said he never heard of the problem. I managed to tighten the bezel enough but I did it so hard I though I was gonna break it.
I did that too, it hepled. But yeah, it is annoying. And it is rattling reflector, not bezel. You can get thicker o-ring and solve this problem (o-ring under the bezel) 
Have you tried switching to 4 brightness mode? Click the side switch 6 times to do that, maybe one of your mode groups is broken.
Unfortunately same problem 
If you put on a thicker rubber O-ring, it will only get worse. The reflector is not pressed by the O-ring, but directly by the glass. In order for the glass to come into contact with the reflector, the glass must first strongly compress the O-ring, which is pressed against the body of the lantern around the reflector.
Now in July 2021, has the ramping mode been smoothed to get an even increase & decrease in ramping? In both the M21-C-U and the M21D?
Controlling the led current by PWM, where the duty cycle control is being applied as linear, would cause this perceived problem. This does apply also in changing the volume of sound, it is a logarithmic power increase for a smooth perception
volume increase; the db scale. that is why older (I date myself) analog volume potentiometers needed a logarithmic taper.
2nd question, are the M21C-U and M21D identical except for the addition of a usb charging port?
Edited in, 3rd question. Since this is an electronic off mode, instead of electrically removing all battery voltage, what is the leakage current in the off mode, typical or maximum??
Thanks, Stan