Paul, Jan,

That caseback is not typical - In fact I've never seen it before. The more common one is the one with the so-called "NATO star" which was Zenith's logo in the 1970s. There is also a plain one which was an option if you wanted to inscirbe your watch. I have never seen the one that Jan has, but the case number is a plausible one so I have to think that it was in some way or other official unless someone substituted it and took the trouble to engrave the case number.

Apropos of the case, once you try that odd cushion case that Zenith used, you will never get it off your wrist - very comfortable and great visual impact.

Typical case backs for all of the steel models of the early El Primero:

: Hi Jan
: That is an amazing example of the A386. Funny thing is that I am in
: the process of buying the exact watch although the backcase on
: the one I am looking at has the 4 point star. That dial and the
: sloping lugs make this a classic. I tried on a friends recently
: and was hooked. It had the same bracelet as Davids. Enjoy
: regards
: Paul
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