This is an old light design, known as the XP-11. I got two from way back in 2013. The body and pill are exactly the same. Here's a couple pics of my mods at the time:
WallBuys still sells it, w/XM-L T6 of course, before the XM-L2's came out, or got popular: http://wallbuys.com/Product/XP-11-CREE-XM-L-T6-700LM-5-Mode-Magnetic-Tail
Here's a thread on it: https://budgetlightforum.com/t/-/22511
UltraFire branded - they upgraded the LED, dunno bout the UI - the stock UI was pretty bad. On the XP-11, the switch is real stiff. It's not protected for accidental activation, but takes a lot of pressure to engage it.
I wasn't a fan of this light - preferred the ZY-T11 clones at the time - did not care for the stiffness of the switch. The pill design is not great for modding, do-able, but you gotta wonder bout the heat mgt - it's press fit basically. Add some thermal grease in there and maybe it would do ok. Also the driver mounted of solder to brass is not ideal.
Amazing how these things get recycled then intro'd as new.