ZENITH EL PRIMERO HW

The history of this Zenith El Primero HW

The Zenith El Primero HW is the hand-wound version of the calibre that the Le Locle-based manufacture unveiled on 10 January 1969, one of the very first automatic chronographs. Founded in 1865 by Georges Favre-Jacot, the company equipped its El Primero with a frequency of 36,000 vibrations per hour – at a time when most calibres ran at 28,800 – to improve its accuracy. In 1996, with classic mechanical watches making a comeback, Zenith took an unexpected decision. It removed the automatic bridge and the entire self-winding mechanism from the movement to create the El Primero 420 calibre, which otherwise retained all the characteristics of the original calibre. Named HW, for Hand Wound, it initially powered a pocket watch – the only one ever fitted with an El Primero – and later the Class Sport range under reference number 02.0500.420. From 2002 onwards, Zenith ceased to officially distribute these models, and the calibre 420 was produced for only a short period.

Case, calibre and strap of this El Primero HW

The 40 mm steel case, 11.5 mm thick, contrasts the polished finish of the bezel with the brushed finish of the sides and lugs. On the right-hand side, the fluted crown, stamped with the Zenith star, is flanked by two pushers. A sapphire crystal protects the black dial, which features large luminescent Arabic numerals and a tachymeter scale around the periphery. Its three blued sub-dials display the small seconds at 9 o’clock, the 30-minute counter at 3 o’clock and the 12-hour counter at 6 o’clock, with a date window between 4 o’clock and 5 o’clock. The hour and minute hands are luminescent, and the chronograph seconds hand is tipped with red. The sapphire case back, engraved with ‘Manufacture Zenith’ and water-resistant to 100 metres, reveals the hand-wound El Primero 420 calibre. With no oscillating weight, its bridges and chronograph mechanism are fully visible, and it beats at 36,000 vibrations per hour, or 5 Hz. The 5-row steel bracelet alternates between brushed and polished links and fastens with a folding clasp. At 11.5 mm thick, the watch slips easily under a cuff.

Why this Zenith watch

Few El Primero chronographs are hand-wound, and the HW was discontinued from the brand’s catalogue in the early 2000s without being reissued. It offers access to Zenith’s high-frequency movement in a rare configuration: an El Primero that is wound each morning using the crown, with a caseback that reveals the chronograph’s entire architecture. Its aviation-inspired black dial remains highly legible thanks to its luminescent numerals, and its 40 mm case retains understated proportions. It offers a glimpse into the history of the El Primero through a little-known variant.

Contents and condition

This watch is supplied in its original Zenith wooden presentation box, with its inner box and instruction manual, but without a warranty card. It has recently been polished, restoring the sharp contrast between the polished and brushed surfaces of the case and bracelet, and shows only slight signs of wear. The chronograph, its counters and the date have been checked and are functioning normally.

Warranty and delivery

The Swiss Collector guarantees the authenticity of this watch, which is covered by a 24-month warranty. We accept returns within 10 days in accordance with our terms and conditions. As Switzerland’s leading second-hand watch retailer, backed by the largest network of shops, we offer online booking for a fitting and collection in-store, or fully secure international delivery.