Arne,

Oh bravo! A very nice one and quite rare indeed, especially in such good condition. I fairly seethe with watch-envy. Zenith was never known for dive watches, although when one finds them, they are lovely, as is this one. This one is Zenith's only use of the inner bezel Supercompressor case, as far as I know, and this model is rated for 200m depth. The engine is the cal. 146, which was Zenith's workhorse chronograph movement prior to El Primero. The cal. 146 is actually a Martel movement which also saw service as the Universal Geneve cal. 285 until Zenith bought Martel in 1960 and embargoed the caliber for its own exclusive use. It drives a huge variety of Zenith models. Thought you've be interested in seeing a sister model of the watch in a 1970-71 Zenith catalog:

all the watches on that page are driven by the 146
and last but not least, a hearty hello from a sister watch:

Lou

: This rare Zenith arrived today...what do you experts say?
: Cheers//Arne Json
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