I am not very familiar with these, but here is what I recall from some things I have heard:

• these are sometimes referred to a "bumpers" because the rotor for the automatic winding swings around on a pivot; it does not make full revolutions, but hits a bumper at either side and bounces back the other direction
• they were not sold in the US and are not shown in the US catalogs, so parts can be scarce over here; still, the watches themsleves seem to come onto the market with some frequency

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: My wife bought me an apparently vintage Heuer
: for an engagement gift. It is a mans
: automatic wristwatch and the seller, who is
: more of a jewellry guy than a watch guy,
: told her it was made around the late 40's.
: Is there any online reference to the
: automatics I could use to identify it?

: It is a mans automatic wristwatch with arabic
: numerals and a case diameter of about 31mm.
: The dial could have been silver or white, or
: maybe off-white, the numerals appear to be
: gold coloured and there is a Heuer logo with
: "Automatic" underneath in the top
: half of the dial and "21 jewels"
: in the lower half. Unfortuantely it leaks a
: lot so the dial is not in the best shape.

: It has a screw back with "swiss made
: automatic antimagnetic" and
: "waterproof all stainless steel
: incabloc" around the edge of the back.
: The number 2550265 is stamped in the back,
: would this be a serial number?

: Ideally I would like to get the watch repaired
: so that it doesn't leak as currently I can't
: even wash my hands with it on. However,
: before that I would really like to be able
: to know what it is. Any help very gratefully
: received, thanks.