So I recently bought some fake ones myself so I thought I might as well write one up to let you know if you bought a fake set.

(these pictures are from this site http://www.nmzol.com/pc/2007/200709/2007-09-04/pc_20070904095932_23392.html)

So the first thing:

The left one is the fake the right one is the real one. Make note of the character to not mix up examples later on.

The packaging is different where the barcode and recycling stickers are missing and the box

is labeled with “STEREO EAR RECEIVER” not “STEREO HEADPHONES”.

Fake:

The real MDR-EX90’s have a metal housing not plastic like the fakes.

Real:

The wire plug us also different where the fake one has the Korea made tag on it.

The real ones are made in China.

That is more or less the guide.

The main sign you got a fake set of headphones is that they are plastic and not made of metal.

Hope this helps.