Spare battery holder for Bose noise-cancelling headsets. Holds two AA batteries and clips to the 5mm cable.
The version supplied may or may not work. TPU is the preferred print filament. Print at 0.2mm layers instead of 0.4mm like I did - the print quality will be much better.
I recommend scaling this design up 1:1:1 by 10%, and using a razor blade to separate the clips from the case. May need to clip the edges of the clips depending on how flexible your headset cable is.
F3D file included if you'd like to make improvements.