Cram a 3600 mAh cell in there and you have a capable Anduril 2 flashlight and a power bank when you need juice for your phone.
That’s exactly the way I use mine, but with LG MJ1 3500mAh cells instead (will probably upgrade to 4000mAh cells from Vapcell or XTAR in the future), much more flexible than a dedicated powerbank, as besides carrying more cells for extended capacity it also does double duty as my backup light (and main thrower if I need one).
I had an issue with its powerbank function about an year ago, but since I have started charging my cellphone while it’s still over 10% and the issue has not happened again.