I would have to say that well over half of torches on Amazon exaggerate their claims by at LEAST 100%. You'll see the same exact 5-mode style with 20 different max output numbers. Most sellers get a counterfeit LED that's half as bright as the real thing, then list the max straight from the CREE spec sheets, ignoring that the numbers come from properly cooled, properly driven, and much more efficient legit bulbs.

Battery sellers on Amazon generally tack on 30-80% capacity, but some go bonkers. Go ahead and search for 18650 batteries for those flashlights. Amazing! Panasonic and LG can't get past 3600mAh for theirs and charge ~$25 for a pair, but multiple sellers have 9000mAh+ options for ~$2/cell. And they ALL have 4+ star reviews. It used to be that the garbage sellers would claim around 3500mAh capacity so that there was some plausible deniability, but now they're probably bordering on nuclear fission energy densities. They're selling a 2 liter bottle of water and claiming there's 3 liters in it.

Oh, and any 'emergency' or safety related product is fair game. If it fails, either they'll rationalize that it wasn't properly maintained prior to the emergency or the buyer isn't around to complain about it.

Needless to say, I don't order anything I actually care about from Amazon. I actually just looked through my 2018 purchases and it reads like the orders I used to place through cheap Chinese sites 5 years ago. I guess I now treat Amazon like a shipping option - $2 premium to get the same junk, but I don't have to wait a month.

As for 18650s I would never buy anything but Panasonic or similar, the risks are just too great, but commingling robs you of the opportunity make an educated decision - you might get genuine Panasonics sourced through Amazon's own supply chain, or counterfeits from anywhere.

A lot of this stuff is obviously coming out of the same factories too... reputable brand X will order Y units of their product, which will be made to spec, then the factory will simply keep the production lines running afterwards with much cheaper materials/components and dump that into the supply chain too. Whether it's electronics or clothing or anything else. It's inevitable at some point that someone will die of hypothermia in a fake North Face jacket when the genuine version would have kept them warm.

On batteries, I just don't buy them often enough to really get screwed over. I try to to get Panasonic or LG, but if it's for a random project I'll look for any that have good review with pictures of the protection board. Then, if they claim something reasonable for capacity, I subtract 30% from that number and buy them if it's in the range of what I need.

As for counterfeits in general... Growing up middle class, counterfeits weren't a bad thing most of the time. Cheaper materials, worse/no warranty, and higher failure rates? Sure. Don't get a counterfeit if it's a matter of health or safety. But, if you could only afford the Thingy X Basic Model, a good counterfeit might mean you could get Thingee X Deluxe Ultra Championship Edition. It might not be as good as the real Thingy X DUCE, but it was usually better than the Thingy X BE.

I never understood the obsession with genuine items in fashion, since most of them were as good or better than the designer versions. Instead of paying $1000 for something, you paid $20 and got the exact same thing with the same materials and slightly different stitches in an unnoticeable location.

People are weird and the topic of counterfeiting really puts that on display.

Some fake products add features, especially the best features from the competitors product that the 'genuine' products couldn't include for licensing reasons.

If you are trying to buy product X and what you get is a fake made with inferior materials, what use are extra features that you didn’t even expect to have?

But seriously, the reason these Amazotrash sellers get away with it is in part due to consumers not actually needing top of the line stuff. So, if you thought you needed 1000 lumen, but in reality you only needed 500 lm, and then get tricked into buying a torch advertising "5000 lm", but it does the job and has extra modes, plus a bike mount, you kinda come out ahead. It also coexists with that old marketing trick used in movie theater concession sizes to get people to spend more than they intended. (Which is the best deal: S: $5, M:$10, L: $12? Most people would opt for medium, but large is only $2 more (at nearly zero cost to the theater).

From that perspective, most of the counterfeits are better because you could either afford more of them or afford counterfeits of higher priced versions. Looking to buy a legit 16GB flash drive for $15, but find a seller with what you think is a legit 32GB version for $15? If it's not broken and actually has 32GB, but is slightly slower than the brand one that was faster than you really needed anyways, seems like a win for you.