Zenith El Primero El Primero Chronomaster Full Open 42 Stainless Steel / Alligator

Reference 03.2081.400/78.C813

Zenith El Primero Chronomaster Full Open 42 Stainless Steel / Alligator

About this watch

The Zenith - 03.2081.400/78.C813 El Primero Chronomaster Full Open 42 is a masterpiece that combines centuries of expertise and innovation with precision and craftsmanship. Its stainless steel case, measuring 42.00 mm in diameter and 12.75 mm in height, exudes refined elegance while showcasing the intricate workings of the El Primero movement through an open case back. The skeleton dial is a visual feast for the eyes, featuring stick and dot indexes and modern-style hands that maintain a clean aesthetic. At its core lies the Zenith caliber El Primero 400B movement, renowned for its precision and boasting a frequency of 36,000 vibrations per hour. This automatic movement offers a power reserve of 50 hours, allowing it to run smoothly without frequent winding. The chronograph feature is where this watch truly shines, with a column wheel mechanism providing smooth and reliable timing capabilities. Paired with an alligator leather strap that complements the polished stainless steel perfectly, this timepiece is not only luxurious but also practical, boasting a water resistance of 100 meters.
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Key Features

  • Stainless Steel Case
  • Sapphire Crystal Glass
  • Automatic Movement (Zenith caliber El Primero 400B)
  • Chronograph Feature with Column Wheel Mechanism
  • Water Resistance: 100 Meters
  • Alligator Leather Strap
  • 50-Hour Power Reserve

Specifications

Brand
Zenith
Family
El Primero
Model
El Primero Chronomaster Full Open 42 Stainless Steel / Alligator
Reference
03.2081.400/78.C813
Movement Features
  • Hours, Minutes, Small Seconds
  • Date
  • Chronograph, Column wheel
Case
Stainless Steel 42mm
Dial Color
Skeleton
Crystal
Sapphire
Water Resistance
100

Current Listings

[WTS] Zenith El Primero Chronograph - Serviced w/Extras

Zenith El Primero Chronograph - Serviced w/Extras

Zenith - 20-0010.420 · $3,350
A Zenith El Primero Chronograph with a gold filled case and 38mm diameter, featuring the Cal.420 movement.

  • Case diameter: 38mm
  • Lug width: 20mm
  • Lug to lug: 45mm
Posted at
Feb 2, 2026, 10:26 AM
Active
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[WTS] Zenith Defy 21 Chroma El Primero (2022) – Ceramic – Full Set – Limited 200 €6950

Zenith Defy 21 Chroma El Primero (2022) – Ceramic – Full Set – Limited 200 €6950

Zenith - 49.9010.9004/01.R947 · $6,950
A 2022 Zenith Defy 21 Chroma El Primero with a ceramic case and limited to only 200 pieces worldwide. It's powered by the legendary El Primero chronograph movement and features an original retail price north of €14,000.

  • Condition: Excellent with minor cosmetic wear on the case near the lugs
  • Case material: Ceramic
  • Movement type: El Primero chronograph
  • Water resistance depth: 100m
Posted at
Feb 2, 2026, 6:19 AM
Active
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[WTS][US] Zenith El Primero Chronomaster Sport - Meteorite Dial - 42mm - 03.3120.3600/76.M3100 - Full Set

[US] Zenith El Primero Chronomaster Sport - Meteorite Dial - 42mm - 03.3120.3600/76.M3100 - Full Set

Zenith - 03.3120.3600/76.M3100 · $13,300
Up for sale is a Zenith El Primero Chronomaster Sport - Meteorite Dial - 42mm Watch functions perfectly mechanically, without issue.

  • Condition: Fantastic condition with minor hairlines
  • Water Resistance: 30m
  • Case Size: 42mm diameter
  • Band Material: bracelet
Posted at
Jan 27, 2026, 8:00 AM
Active
View listing on r/WatchExchange
[WTS] Brand New Zenith Chronomaster Original Reverse Panda El Primero Chronograph | 03.3200.3600/21.C903 | Full Zenith warranty | Price reduced

Brand New Zenith Chronomaster Original Reverse Panda El Primero Chronograph | 03.3200.3600/21.C903 | Full Zenith warranty | Price reduced

Zenith - 03.3200.3600/21.C903 · $7,150
A brand new Zenith Chronomaster Original Reverse Panda El Primero chronograph, discontinued by the manufacturer, still in its protective stickers and under full warranty.

  • Condition: Brand new, never used
  • Warranty: 2-year warranty from Zenith
  • Strap: Original leather strap with deployant clasp
Posted at
Jan 25, 2026, 4:06 PM
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[WTS] Zenith El Primero Defy Extreme Diver AKA PURE WRIST JOY Ref 95.9601.3620/51.I301 FULL SET

Zenith El Primero Defy Extreme Diver AKA PURE WRIST JOY Ref 95.9601.3620/51.I301 FULL SET

Zenith - 95.9601.3620/51.I301 · $7,950
A Zenith El Primero Defy Extreme Diver with a unique blue starry sunray pattern dial and a titanium case.

  • Condition: Pre-owned, barely over a year old
  • Case size: 42.5MM diameter
  • Movement: El Primero cal 3620 CS automatic movement
Posted at
Jan 24, 2026, 7:53 PM
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[WTS] Zenith El Primero Chronomaster Revival Panda 03.A384.400/21.C815

Zenith El Primero Chronomaster Revival Panda 03.A384.400/21.C815

Zenith - 03.A384.400/21.C815 · $5,999
This is a 37mm Chronomaster Revival Panda, a limited edition model from Zenith's El Primero series, featuring a classic panda dial.

  • Condition: preowned clean condition with hairline scratches throughout
  • Crystal condition: may contain marks under strong magnification
  • Strap condition: worn
  • Case size: 37mm
Posted at
Jan 23, 2026, 6:51 AM
Active
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[WTS] Zenith Defy Skyline Chronograph - Full Set - El Primero 3600 - $9,200

Zenith Defy Skyline Chronograph - Full Set - El Primero 3600 - $9,200

Zenith - 03.9500.3600/01.I001 · $9,200
The Zenith Defy Skyline Chronograph features a silver 'starry sky' dial, a 1/10th-second chronograph with a central chrono hand that makes one full lap every 10 seconds, and a versatile design with a quick-change system for the bracelet and strap.

  • Condition: Excellent overall Condition
  • Movement: Zenith El Primero 3600 (5Hz / 36,000 vph) with 1/10th-second chronograph
  • Case size: 42mm diameter
  • Bracelets/straps: Steel bracelet and green rubber strap with Zenith quick-change
Posted at
Jan 20, 2026, 7:23 PM
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[WTS][US] Zenith El Primero Chronomaster Sport - Meteorite Dial - 42mm - 03.3120.3600/76.M3100 - Full Set

[US] Zenith El Primero Chronomaster Sport - Meteorite Dial - 42mm - 03.3120.3600/76.M3100 - Full Set

Zenith - 03.3120.3600/76.M3100 · $13,350
A Zenith El Primero Chronomaster Sport watch featuring a meteorite dial, in 42mm size.

  • Condition: Fantastic with minor hairlines
  • Case size: 42mm
Posted at
Jan 20, 2026, 7:08 AM
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Zenith 42mm El Primero Chronomaster Open Heart Stainless Steel Complete

Zenith 42mm El Primero Chronomaster Open Heart Stainless Steel Complete

Zenith - 03.2040.4061/69.C496 · $4,950
A Zenith El Primero Chronomaster Open Heart chronograph watch, featuring a 42mm stainless steel case and in-house Caliber Zenith El Primero 4061 movement. The watch is dated October 2014 and has been recently serviced by Zenith.

  • Condition: Mint Condition with light hairline scratches only
  • Case size: 42mm diameter
  • Water resistance: 30m depth rating
Posted at
Mar 31, 2025, 1:26 PM
Active
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