This is a shutter that ran for a year or 2 in 1969 - 1971 time frame, and it is a direct replacement for any Schneider lens that came in the Compound 3 or size 3 barrel with 56mm threads. Modern lenses are 58mm thread.
From memory, some of the lenses that would have come in the Compound 3 would be 210mm f4.5 Xenar. 300mm Convertible Symmar. 210mm Angulon. And everyone's fave, the early 355mm G-Claron.
One other oddball which is really neat is the 210mm Coated Voigtlander Heliar. Never tried it, but perhaps the 210 f4.5 Lanthar would be a direct fit also since it's a glorified Heliar. These are all direct fit, no machine work necessary. My keeper Heliar is in one of these.
This shutter has 56mm threads, but what also makes it unique is the long boss area beyond the flange threads which is the same distance body to body as the Compound. All later Copal 3's and ones used by other brands didn't have the careful distances that made them interchange with the Compound and #3 barrels.
This shutter is near mint and the speeds sound impeccable. I'm into it at [SIZE=3]$345[/SIZE] + shipping