IMPORTANT: Please print without supports.
This is an adapter I designed to mount Koss Porta Pro headphones to the Oculus Rift S VR Headset. Just pop the Koss speakers off of their original frames and press them into the 3D printed arm parts, making sure to keep the left and right correct.
The bracket parts slide onto the outside of the headset bands. Push them toward the front of the headset to secure them in place. I've provided various levels of tension for how much they grip the arms when inserted. The t25 level worked best for me, but you may want to print all of them and see what works best for your printer setup.
If you need more tension variations, let me know in the comments and I'll try to help.
On a side note, this design is not perfect. Ideally you'd want the headphones to flip outward, like the original Rift, to allow for easier headset donning/removal. I'm not sure I'll get around to figuring that out, but feel free to remix the project.