I recently purchased a new old stock NI GPIB-USB-HS adapter from eBay. The seller claims it is a genuine NI device.
Comparing it to the images on
TiN's website, I would guess that my unit is a counterfeit, because there is no metallization on the inside of the plastic enclosure. The GPIB connector also has slight play (the enclosure doesn't pinch it tightly enough, something that would be taken care of by the EMC gasket in the picture of TiN's unit). Attached below is the image of my unit.
I reached out to NI for their opinion on the matter and contrary to what I expected, they believe my unit is authentic.
Please, put my mind at ease, if you happen to have access to one that was purchased through official NI channels. Check inside (you can unscrew the enclosure without leaving a mark on the device) and see if your unit has metallization on the inside like TiN's unit does.
I don't want to figure out a year from now that my unit failed because it was a cheap Chinese clone (that I wasted 400€ on) and at the same time, I do not want to hassle a legitimate eBay seller without unquestionable evidence that he sold me a knock-off.