It is rare, but some fake products due get through even if you always get things fulfilled by Amazon. I've never had the problem myself in years of buying thing

It is rare, but some fake products due get through even if you always get things fulfilled by Amazon. I've never had the problem myself in years of buying things including PC parts via Amazon, though a friend has. (we are both in the UK) Due to the way things are co-mingled in the warehouses there isn't really much distinction between “sold by Amazon” and “fulfilled by Amazon”: if something has the same product code the system assumes it is the same thing, so the picker is sent to the closest one on the assumption that they are the same thing. In my friends case this resulted in him getting a counterfeit SD card. He noticed oddities on the packaging before actually opening it, so we don't know how far it was from spec. The return process was smooth and the right product was received the next day, but it was a faf he could have done without and if he'd not noticed he might have had a shock later if the card corrupted itself after writing a small amount (many fake storage devices pretend to be far larger than they are and stop writing (or worse: data is silently corrupted) once you approach their real size). Luckily it wasn't needed urgently, so the extra day wasn't a massive inconvenience.