I tried with Samsung 50E and 40T - both work fine. Although I’ve put things together by myself but I assume stock version will take 21700 as well. Some “protected” 18650 are 5-7 mm longer so most of producers take it into account. Just pay attention your 21700 is 70mm long, not more. Which means it must be unprotected which (IMHO) is better. But I would recommend to use it with the adapter. S11 can take 26650 which means 21700 may rattle inside. The difference between 26650 and 21700 is 5mm, while between 21700 and 18650 is 3mm. When you bump your flashlight - this may make a difference.
Yes, I noticed this on my M21C-U for 4 mode. This happened on high mode turn off(memory) and turn on again. It also happened for from off, double click to high.
I did some testing. This happened when battery is 3.8 volt and below. With a fresh battery, everything is fine.
I just received my L21A CULPM1 last night! I wanted to say these things -
1. this was my first order from you, and my first convoy products (also got m21a CSLPM1) and they are fantastic! Build quality, threading, packaging, and looks. all awesome.
2. I received this order in 18 days to Eastern USA! I think that is amazing. No BS, just order and ship. Really appreciate that!
3. Both lights are VERY impressive! They both throw massively! The M21A with CSLPM1 is iconic - 21700 battery, C8 size, Super light and pocketable, and out throws all others close to its size i have. Look forward to having this as a go to light.
4. The L21A is a TOOL, it is solid, and very nice looking and seemingly unbreakable. Easily programmed it to my desired setting (#10). This thing throws easily with my other throwers of $100+. i couldn’t be happier.
An even cloverleaf is a good indication it’s well-centered. Any “irregularity”, eg, 2 short and 2 long, only 3 lobes, etc., generally means it’s a bit off-center.
The smaller the chip, the more critical it is to center it, and the harder it is, too.
It is pretty even with 3 leafed clover, so guess it is well centred. I tested it yesterday and am pretty impressed for this small form factor to be. Will keep it as is. Also considering to buy L21A or the upcoming SBT 90.2.