Binocular stabiliser.

To add an extra point of contact on the forehead.
Seems to help a tiny bit. Tried to make focus knob accessible.

Made this to fit me, including source FreeCad file for customizing.
Fits me and my Vortex Diamondback HD 10x42.

Additional items required:
Camera screw (the one that fit an SLR to a tripod).
(Binocular with aforementioned thread.)
M3 bolt with nut. At least 17 mm without head.
I made my test print with 0.8 mm walls and 20% infill.
I would recommend 1.2 and 30 for real deal.

WIP for now since I've not tested it properly.