Bob, just to complete the thought: Neumann hasn't made capsules like
that in decades, and they ran out of replacement parts stock a long
time ago--which is no surprise, since the ultra-thin nickel foil is
easily perforated.

Thus if the capsule of a KM 56 needs replacement--which many of the
ones on the used market seemingly do need--you have only some rather
poor choices: "reskinning" with unpredictable sonic results, versus
looking around for a genuine Neumann replacement capsule which will
probably cost you around $1000.

I would never buy one of these without a guarantee based on an expert
third-party inspection; there are too many rejects floating around, and
too many "vintage" equipment dealers who have played fast and loose
with their verbal descriptions and in some instances, with the parts
inside the microphone case.

--best regards