Purchasing convoy s2 - few questions

I’m about to pull the trigger on the convoy s2 (u2 driven at 2100ma), but I thought I’d clarify a few things lest I regret my purchase later.

1 - will it fit keeppower 3400mah protected cells? And if not, will the convoy s3 fit them?
2 - what type of battery life on the high mode am I looking at? Is it as simple as dividing the capacity of my cell by 2100?
3 - does it tail stand?

I’m sorry if these questions are stupid, I’m still a beginner to flashlights :s

Cheers!

1 - Yes, the S2 has springs at both ends of the battery, and it will (barely) accommodate a keeppower 3400.
2 - I usually guesstimate about 75% of the battery rating; e.g. (3400 mAh)/(2100 mA) = 1.6 hr; 1.6hr * 0.75 = 1.2 hr estimated runtime
3 - Yes, it tailstands. The lanyard can get in the way, depending on how it is attached, but there is a relief slot in the tailcap for the lanyard.

No problem with the questions, hope this helped!

For #2, I should have pointed you at HKJ’s excellent review:
https://budgetlightforum.com/t/-/10059
You can go to the “discharge, time” graph, find the light blue 2.0A curve, and see that the battery voltage will hit 3.3V at about 1.25 hr, and reach low-voltage cutoff at about 1.5 hr.

Go for it! I just received mine, S2 U2 1B 2100mA, and its very good quality/value for money! Panasonic 2900mAh protected fits, no extra space though! It gets warm on high, but should be ok. The s3 is 9mm shorter, so dont know if protected cell fits.
I like it very much and recommend it!

PS- It tailstands, but not steady because of the rubber tailcap (at least mine).

I have an S2 2100. I really like it, but ordered another but 1050 maH. I like the U2 tint better than the 7C which was a little too yellow. The U2 is great.
I wanted run time over throw, however, I cannot tell that much difference in the throw of the two.
I have some Panasonic protected batteries from FT, and they fit fine.

The lights are good and the price is also. Both get pretty hot on even med, but the 1050 mah is better and much better on low.
Jerry

The S2’s with the 105c drivers (2.1a, 2.8a) have a shorter spring that is found on their nanjg 105c drivers (Like this one https://www.fasttech.com/products/0/10001683/1122302-8-amc7135-4-group-25-modes-led-flashlight-driver-c) instead of a bigger spring.

This means that unprotected cells won’t work on the stock S2 2.1a and 2.8a without modification. Luckily the isolator for the tail-cap spring holds it back a bit and when removed it works with unprotected cells pretty well. My xtar 2600 sits about level with the body tube on my 2.8a L2 height-wise and has some (But little) lateral play.

Just my .02c. I bet the S2 105c would deal better with longer cells to a point but I don’t know if the stiffer springs would ultimately lead to battery crushing easier than the taller softer ones.

My xtar barely fits into my M2 however it does fit and I blame the longer springs for most of that; it has a pretty sizable chink that sticks out of the tube when it’s in but the M2 does seem of notably heaver and better quality.

The S2’s pretty darn good for it’s price and it doesn’t really fib on the output (Solid nanjg’s) but it could do with some better programming and a rethink on the tail cap. I must say though that the retaining ring was notably better on the tailcap than I though it would be, nice and beefy for what it is.

Thanks for the detailed replies guys, purchased it!

Must stop buying stuff now, I spent ~$90 last night on an olight s20/xtar wp6 ii/2xkeeppower 3400, lol.