Microscope Crash Preventer for Wild Heerbrugg M400 Photomacroscopes/M420 Macroscope Stand
38mm OD x 71mm Long (The outer diameter varies from 37.96mm on one end to 38.04mm on the other)
1.5" OD x 1" ID
Outer diameter just under 1.5"
Inner bore just under 1"
Seems to be anodized nicely black and the edges are beveled smooth for easy handling
Maybe this is for a Leitz extension of some sort 38mm - for linking part of a trinocular head to a camera adapter base???