Mine is in the Copal 3S, so I was going on memory for the other shutter's name. Probably should have looked it up. It fit just fine in a regular C3 drilled lensboard. From what I've seen, the Shanel shutters are marked for both the 21/4.5 and 25/4.5, so you could get both lens cells and switch back and forth between the two lenses with that setup.
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