My own experience of counterfeits includes, of all things, water filters. The packaging was perfect, but the filters literally wouldn't fit without modification.

I gave up after the third time and went back to buying from brick-and-mortar, and haven't had a problem since.

Between my experience and reports from others, I'd say that you've been extraordinarily lucky.

There's a philips respironics CPAP face mask shipped in a ziploc bag with a philips respironics sticker on it.

Other gear (filters, nose cusions, tubing) looks more or less authentically packaged correctly.

lucky and/or possibly unaware

And I used to buy SD cards and Mac adapters from Amazon for work and it was about half of them products were fake until I finally stopped and got them from cdw. They would fight me every time I brought it up. It is well know issue glad you never dealt with it.

How do you know?

Some of the fake stuff is pretty good. Would you notice if your energizer batteries were random Chinese fakes?

The first fake I discovered on amazon was a mouse trap of all things.

Batteries (as energy storage devices) are a great example of something I wouldn't want to be counterfeit. A poorly made battery has a better chance of starting a fire. Probably not going to happen with AAAs, but larger cells like 18650s might be worth a worry.

I probably wouldn't care about a mouse trap though, as long as the mechanism doesn't store enough energy to burn my house down.

+1 to this

My friends and I all bought fake Bose headphones from a shady dealer in China (in person), and the $50 knockoffs sounded exactly as good as the real $600 ones. The only way to tell there was anything wrong was by the fact that they all broke down within a few months.

So one thing to keep in mind is there is a lot of “leakage” out of genuine products manufacturer in China and SE Asia.

Workers will “divert” product from factories (or almost) finished product and sell on the side.

I’ve heard this is a big issue with clothing manufacturers.

Of course determining whether it’s actually counterfeit or just diverted product is likely impossible at the point of purchase.

Right, and I would assume that a good fraction of those were products that didn't qualify as "good enough" at the factory ?

Still, for value conscious people it’s fine. My dad was really into shortwave radio and other stuff in the 80s.

He’d buy “grey market” gear from stores in NYC that were legit, but intended for Latin America or other markets. Sometimes the fit and finish would be interior or connectors would be lower quality, but the price was right and an 80% product is better than nothing.

If I know I’m buying a “Rolox”, that’s one thing. If you sell and price a Rolex that is not, that’s a problem.