GoPro mount for a 16mm boom tripod (microphone or cymbal stand?)

thingiverse

For some reason I ended up with this tripod (20 years or so ago I guess) but without the boom that presumably would have gone into it. There was a black steel insert to hold a bolt though. Maybe it's a cymbal stand from a drum kit, if not a microphone stand. After removing the black insert, the hole is 16mm. So I made this insert to mount GoPro-compatible stuff; the first use case is for mounting a laser projector.