Jetbeam RRT-2 with flat-end 18650s

:tinfoil:Hi All,
this is my third post here. (yes! I'm a rookie).
I was trying to find the answer for my question here but didnt find myself lucky.
I am in process of ordering a Jetbeam RRT-2 and I was wondering if AW 18650 2600mAh with flat ends will work for me. I read that some flashlights fail to work if batteries are missing the + nipple. I know there is a fix for it (adding magnets or ...) but without any modification, dose Jeatbeam RRT-2 a flat-end battery friendly?
Also if you can recommend me some other brands of batteries that have longest runtime, slowest discharge speed and the most rechageable life time.
Thank you all,
E.

Yes, flat head works. But if you're looking for alternatives, AW batteries seem to be the most recommended here.

I have the same light and batteries and they work fine.

Thank you