Zenith – El Primero A3817 Original 1971 Steel Chronograph – Cal. 3019PHC ON HOLD / RISERVATO

Among the early El Primero references, the A3817 is the exception. The first-generation El Primero split into two families: the angular steel tonneau cases of the A384 and A385, and the round A386 with its now-famous tricolour overlapping counters.

The A3817 is the only period reference to combine the two — the sharp tonneau case of the sports models fitted with the tricolour “A386” dial. It was made for a brief run in 1971, in a quantity Zenith SA has confirmed at 1,000 examples, against 2,500 for the A386. It is, simply, one of the scarcer early El Primeros.

This watch is in very good original and untouchedcondition. The case measures 37.4mm excluding the original crown, 47.2mm lug to lug, and is unpolished — edges sharp, original finishing visible, caseback serial legible.

The tricolour dial with overlapping counters is in excellent condition, showing a light, even patina, with a quick-set date at 4 o’clock.

Look closely at the outer chronograph track and you’ll find the detail that sets this watch apart from almost every other chronograph of its day: the pyramidal “shark’s tooth” scale, 300 triangular graduations that, counting the divisions between them, mark out 600 steps around the dial. This is not decoration. The El Primero beat at 36,000 vibrations per hour — 5 Hz — and was the only automatic chronograph of its generation able to measure to a tenth of a second.

Rival chronographs, running at 18,000 or 21,600 vph, could not resolve time that finely, and their dials could not carry this scale. The shark’s tooth track, found in period only on the A3817 and the A3818 “Cover Girl,” is the dial’s declaration of what the movement beneath it could do.

Hands and luminescent material are original and untouched

This watch is complete with its original Gay Frères steel ladder bracelet, dated 4/71 and approximately 20cm in overall length, în a strong, lightly used, condition

this watch will be delivered with our six-month guarantee and certificate of originality.

Worldwide shipping is available and inquiries are welcome.