Step-Case ‘Tasti Tondi’ Longines 13ZN

Round pushers on a 13ZN and you’re definitively in the cognoscenti, no matter where you’re turning up. Raj Chaudhuri wrote an exceptional article for ACM last year titled ‘Is the Longines 13ZN still collectible?’. The answer, if community enthusiasm is anything to go by, is yes. It certainly deserves to be. But we’re very much in a buyer’s market for chronographs like this in 2023. That’s a good thing for the thicker-skinned, as the market is throwing up some ridiculous value propositions right now, amongst them this 30s flyback chronograph with one of the most innovative calibres of all time, sub-20K in USD. Hard to argue, honestly.


The 13ZN was amongst the first chronographs to not be a monopusher, before Breitling patented two pushers in 1934. It was born from the needs of aviators, for whom a flyback is extremely useful for calculating distance traveled or firing lengths without missing the second that restarting the mechanism takes. The flyback on wrist was nonexistent from other manufacturers of the time until the Breguet XX took over. This was because Longines held the patent, throughout the second World War. Despite the 13ZN and earlier 13.33Zs being known mostly for their flyback functionality, some of the earliest 13ZNs are simple chronographs without a flyback complication. This 1936 chronograph is one such (quite rare) example.


Collecting the 13ZN is a study in patience and education. There are near infinite iterations of dials, hands, and case variety. While they’re all two-pusher and two-register, that’s about it. The pusher shape changes, dial color and style, scales, handset style, lume, it all changes. Cases could range all the way from 34 to 38mm in all lug styles. There was extensive hand finishing employed on each movement that was highly varied watchmaker to watchmaker. This is highly varied watchmaking from watchmaking’s golden era, driven by purpose. And it’s a favorite of Goldberger. Whether it is or isn’t collectible in modern times, it should be.


This example features a silver dial with blued steel hands, 34mm steel case, and straight tapered lugs. All radium is present in great nick, no idea if it’s been touched up but seems possible. The caseback bears a deep engraving celebrating the 50th birthday of someone named Grety in German. A great watch at a great value, out of Shanghai.

Find this 13ZN here from Woohoo Time for 16700 USD.