Wish.com sells 90000000 lumen flashlights, 800000 watt solar panels, 6000 mAh 18650 batteries, and 2 TB flash drives. Apparently truth in advertising does not apply to sellers outside the US.
On a whim, I bought some 18650 batteries from wish that were obviously fake. There is no 18650 battery made that is larger than 3600 mAh. The cells from wish.com are rated 6000 mAh but my Opus tester showed they had a fraction of that, maybe 400 mAh. Most of the off brand 18650 batteries are from disassembled laptop batteries that have been resleeved. UltraFire gets a lot of bad rap but if you buy the batteries from a reputable seller you will get the real deal.