Not sure if these deserve their own thread or should be piggybacked elsewhere... https://www.superbestaudiofriends.org/index.php?threads/fostex-t-x0-ii-headphones.7972/ They're basically a kit with MKII headband, MKIII drivers, various dampening materials, two sets of ear pads, and two cables. One of the fellas here posted an ebay link of these open box kits from the UK ,and they accepted my offer of $100 shipped. Everything in the pic below was included, the sticker packs as well, and they appeared to be brand new. The instructions have an English explanation of the various dampeners and mods. Since these are the MKIII drivers with the little window on the back side dampening material, I was surprised to see a tiny piece of foam that can be plugged into that spot that "dampens lower frequency". I haven't tried that option yet though. All in all a fun mini project for dirt cheap that took me back to the roots of my addiction to this hobby. Here are a few quick raw measurements I took. The drivers are matched quite well, with a slight leak probably being the culprit of the different low end between channels. Also during a frequency sweep I could hear the Right driver slightly flutter down low and it shows up in the distortion plot as significantly higher down there than the Left. By the way this kit retails for $250-300ish USD, so $100 was an absolute steal. EDIT: I forgot to add I took measurements with the denser under ear pad foam, slim angled pleather pads, and all dampening material installed as per instruction.