spucky117Mine also have the 600ohm mark on the plastic part of the end of the cord (the part that plugs into your device.) Not only was it on the box but it is also on my headphones. I am not complaining. It is either that they are the 250ohm and its a misprint (most likely given my experience with them) I use the same DAC/AMP chip but mine is from JDS labs. Since I have listened to them both amplified and not, I would say that they are probably just misprinted. If we did get the 600ohm version its a free upgrade, so I wouldn't worry about it, but I am curious.