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The Zenith Pilot Doublematic reference 03.2400.4046/21.C721 packs world time, an alarm, a chronograph and a large date into a 45 mm steel case. It is discontinued, and the available hands-on review offers a useful perspective on its scale—but not a substitute for trying one on. Its defining appeal is the unusual number of functions; its defining trade-off is the substantial wrist presence needed to house them.
What is the Zenith Pilot Doublematic?
The steel Doublematic is reference 03.2400.4046/21.C721. Zenith’s Osaka boutique identified the model as discontinued in a 2020 listing, which gave a 45 mm case and 5-atmosphere water resistance (Zenith Boutique Osaka). Rose-gold examples use a different reference, 18.2400.4046/01.C721; specifications for one material should not automatically be applied to the other (Zenith reference listing).
Inside is the automatic El Primero 4046. Published specifications describe a 50-hour power reserve and a 36,000-vibrations-per-hour (5 Hz) frequency (WorldWatchReview; Quill & Pad; WatchBase). Those figures describe the movement’s published specifications, not a measurement of an individual watch’s current performance.
What does the Doublematic do?
The watch puts four headline functions on one dial. The displays are useful in principle, but the number of hands, counters and indications also makes the layout information-dense.
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- Automatic movement
- Stainless steel case
- Brown leather strap
- Pin buckle
- Water-resistant to 165 feet (50 M)
| Function | What it provides |
|---|---|
| World time | A city ring and day/night indication show time across 24 time zones (WorldWatchReview; Quill & Pad). |
| Alarm | A dedicated setting hand and on/off indication accompany a second barrel for the alarm and an indication of its remaining reserve (WorldWatchReview; Quill & Pad). |
| Chronograph | Central chronograph seconds and a 30-minute counter provide elapsed-time measurement (WorldWatchReview; Quill & Pad). |
| Date and alarm reserve | A large date sits beside the chronograph counter, while a separate display indicates the alarm barrel’s remaining reserve (WatchBase; Quill & Pad). |
How does the Doublematic alarm work?
The alarm has its own setting hand and an on/off indication. Its separate barrel is distinct from the watch’s timekeeping reserve, and the dial includes an indication of the alarm barrel’s remaining reserve (WorldWatchReview; Quill & Pad). That second energy source is what makes this more than a conventional chronograph with a world-time display.
The exact setting and activation sequence is not established here. Zenith’s manuals and support page offers general resources for watches acquired before 2025 and support contacts, but it does not establish a Doublematic-specific manual or control sequence. For an operating example, request the correct instructions from Zenith or a qualified watchmaker rather than experimenting with the controls.
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What is the steel reference’s size and water resistance?
Tim Mosso’s 2024 review lists the steel watch at 45 mm in diameter, 15.7 mm thick and 53.3 mm lug-to-lug, with 22 mm between the lugs and 50 m water resistance (Quill & Pad). Zenith Boutique Osaka’s 2020 listing independently reports 45 mm and 5 ATM for the model (Zenith Boutique Osaka).
These published dimensions make fit a question of more than diameter. Lug-to-lug span and thickness affect how the watch sits and how much it stands above the wrist; compare all three with a watch you already find comfortable. The reported 22 mm lug width is a useful starting point for strap searches, but it does not establish compatibility with every strap end, taper or clasp.
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- Black small second dial
- Brown leather strap
- Swiss-automatic movement
- Case diameter: 40mm
- Water resistant to 330 feet
In his 2024 review, Mosso says the watch would be too large for his 16 cm wrist. That is one reviewer’s experience, not a universal fit rule. The 50 m/5 ATM figure is a stated rating, not proof that a particular older or unserviced example is safe to wear in water; condition and inspection matter.
What did the Doublematic cost, and what is it worth now?
Published historical prices differ, so they should not be treated as a single definitive launch price or as a current valuation.
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| Amount | Context |
|---|---|
| $16,400 | WorldWatchReview’s reported stainless-steel launch price in 2012 (WorldWatchReview). |
| $13,200 | Quill & Pad’s cited 2012 retail price, included in its 2024 review (Quill & Pad). |
| $9,950 | Quill & Pad’s pre-owned price snapshot in its 2024 article; it is not a current market valuation (Quill & Pad). |
| ¥1,815,000 | Zenith Boutique Osaka’s Japanese retail listing, including tax, in 2020 (Zenith Boutique Osaka). |
The two reported US-dollar launch-era prices conflict, and the available sources do not resolve the discrepancy. Current inventory, asking prices and completed sales are not established by these historical figures. To assess a present-day example, compare listings and recent completed transactions for the same reference, accounting for condition, service history, completeness and seller protections.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What to check before buying a used Doublematic
Because the model is discontinued and combines several complications, a listing’s reference and condition deserve close attention. Before committing, ask for:
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- Clear confirmation that the watch is the steel reference 03.2400.4046/21.C721, not a rose-gold variant or another model.
- Documentation of service history and a recent assessment from a qualified mechanical-watch professional.
- Evidence that the chronograph, world-time display and alarm operate correctly; ask how the alarm reserve indication behaves.
- Condition details for the case, crystal, dial and bracelet or strap, plus what is included with the watch.
- A current price comparison with condition-matched examples and clear seller safeguards.
Zenith’s manuals and support page is the documented general starting point for service contacts and resources. The cited sources do not establish a model-specific service program, so confirm repair capability and parts support directly before purchase.
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Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
