KSC75 on a Porta Pro headband. Something about this simplicity, porta(heh)bility and comfort makes me want to use this combo more than my HE400SE, KZ ZSN Pros, or my Akg M220. :
Introducing: KPH40 Utility – Koss Stereophones
Another Koss KSC75 + Parts Express headband mod : r/headphones
YunYiYi 2 Pairs Black Replacement Sponge Headband Head Band Foam Pads Cushions Repair Parts Compatible with Koss Porta Pro PP Headphones Headset: Amazon.co.uk: Electronics & Photo
How to do the Headband mod for Koss KSC35 Headphones and Koss KSC75 Bluetooth headphones - YouTube
Replacement Headband for Koss KPH30i by Dope-Johnny | Download free STL model | Printables.com
The Koss KSC75
Koss KSC75 Compatible Headband (Parts Express)
Koss P/21. Disappointment, but nice headband and Pads for modding : r/headphones