This is an odd shutter for a 'quad camera'. It appears to be a Ilex #5 but the shutter has only 4 blades for the 4 holes.
It works perfectly even at the slow speeds and B and T.
This includes the mounting ring which normally sells for $50 itself.
There must be some great parts here.
Start it out at $50 asking price and see if anyone is interested.
i just photographed it with the blades open. The blades are big cuirved triangles like you would expect from a leaf shutter but they are made to only cover the 4 holes.
I'll take a pic tonight with the blades closed.
Like I said, it works perfectly.
May be interesting to use as it is for some bokeh-softening effect like you would get from the iris of a imagon.