Hey @Zedkah, happy to share!
Itâs a standard mechanical part called a âShaft Collarâ (in the UK, it may have a different name in the US). They usually come with a grub for fixing to a bar, which I swap out for a standard bolt.
The ones I use are 10mm wide, with a 10mm internal diameter, a 20mm external diameter with an M5 bolt hole. Most importantly theyâre stainless steel - I tried a couple of options and this seemed to be the best for acoustic transfer, significantly more expensive than acrylic or non-stainless steel though. I think due to finish / materials / quality I ended up paying nearly 2 quid each one, as bulk prices didnât really make a difference until you needed over 100 of the buggers (Which I didnât need. I mean the modules sold well, but not THAT well).
I presume someone must also make these in brass, but I wanted the whole module to be silver.