Zenith Defy El Primero 21 Buying Guide, Specs & Prices | Ultimate Watch
The Zenith Defy El Primero 21 is the watch that took the 1969 El Primero idea to its logical extreme: a mechanical chronograph that measures and displays 1/100th of a second, with a central chronograph hand that sweeps a full lap of the dial every second. Zenith launched it at Baselworld 2017, and it remains one of the very few series-produced mechanical watches that can time to a hundredth. The trick is that the movement, the El Primero caliber 9004, runs two entirely separate escapements and gear trains: one at 5Hz (36,000 vph) for the time, and a second dedicated chronograph escapement screaming at 50Hz (360,000 vph). We handle these across our counter at 19 West 47th Street regularly, both buying and selling, and collectors either love the theater of that second hand or find it too much. There is very little middle ground, which is exactly why the market on them is worth understanding before you buy or sell one.
Specifications
History
Iconic References
Buying Guide
Pricing & Market Data
Cultural Significance
Collector's Lore
The party trick everyone shows off is starting the chronograph and watching the central hand blur into a full one-second lap of the dial. It genuinely looks like the second hand is spinning like a fan blade, and it is the single most common reason people buy the watch after seeing it in person. The engineering lore is the twin-escapement architecture: two separate power sources and gear trains in one caliber, with the chronograph escapement sitting dormant until you engage it, so the timekeeping side is not drained by the 50Hz monster next to it. Collectors also note that the microblasted titanium finish, part of the watch's stealthy modern look, is the first thing to show wear, so genuinely crisp unpolished examples stand out. The Defy 21 is remembered as the watch that proved the El Primero name still had a technical frontier left to push almost fifty years after 1969.
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