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.
Buy Now on Jomashop
This is an affiliate link

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 Tipo CP-2 Chronograph 03.2240.4069, Underrated El Primero Beast (641/1000)

Zenith Tipo CP-2 Chronograph 03.2240.4069, Underrated El Primero Beast (641/1000)

Zenith - 03.2240.4069
Zenith Tipo CP-2 Chronograph 03.2240.4069 is an underrated El Primero beast, one of only 641 pieces produced out of 1000.

  • Condition: Underrated
Posted at
May 15, 2026, 9:21 PM
Active
View listing on r/WatchExchange
[WTS] Brand New 2025 Zenith Chronomaster Original El Primero Chronograph Reverse Panda | 03.3200.3600/21.C903 | Price reduced

Brand New 2025 Zenith Chronomaster Original El Primero Chronograph Reverse Panda | 03.3200.3600/21.C903 | Price reduced

Zenith - 03.3200.3600/21.C903 · $6,800
A brand new, discontinued Zenith Chronomaster Original Reverse Panda chronograph watch, still in its original packaging and with a full 2-year warranty.

  • Condition: Brand new, never used
  • Material: leather
  • Strap size: unknown
  • Warranty duration: 2 years
Posted at
May 14, 2026, 11:52 AM
Active
View listing on r/WatchExchange
[WTS] Zenith Defy El Primero 21 • Titanium • Skeleton • Full Set • Serviced

Zenith Defy El Primero 21 • Titanium • Skeleton • Full Set • Serviced

Zenith - Defy El Primero 21
This listing is about a Zenith Defy El Primero 21 watch with a titanium case, skeleton design, and full set. It has been serviced.

  • Condition: Full set
  • Material: titanium
  • Movement: El Primero 21
Posted at
May 14, 2026, 10:03 AM
Active
View listing on r/WatchExchange
[WTS][US] Zenith El Primero Chronomaster Sport - White Dial - 41mm - 03.3100.3600/69.M3100 - Full Set

[US] Zenith El Primero Chronomaster Sport - White Dial - 41mm - 03.3100.3600/69.M3100 - Full Set

Zenith - 03.3100.3600/69.M3100 · $7,500
Up for sale is a Zenith El Primero Chronomaster Sport - White Dial - 41mm that functions perfectly mechanically without issue.

  • Condition: Fantastic with few hairlines on clasp, case, and bracelet
  • Case size: 41mm diameter
Posted at
May 14, 2026, 7:25 AM
Active
View listing on r/WatchExchange
[WTS] Neo Vintage French Military Zenith El Primero Flyback Chronograph Ref 02.0470.405/25 FULL COLLECTOR SET

Neo Vintage French Military Zenith El Primero Flyback Chronograph Ref 02.0470.405/25 FULL COLLECTOR SET

Zenith - 02.0470.405/25 · $4,250
This is a unique Neo Vintage French Military Zenith El Primero Flyback Chronograph, featuring a matte black dial and stainless case. The watch comes in a collector's box and papers set, including an original serialized hang tag.

  • Condition: really nice condition, with wear throughout
  • Case size: 40mm diameter
  • Bracelet length: fits up to app 7 inches
  • Movement type: automatic chronograph with quickset date winding
Posted at
May 11, 2026, 8:57 PM
Active
View listing on r/WatchExchange
[WTS] Zenith Defy Skyline Chrono Silver - El Primero - Full Set 2024 - Integrated Bracelet & Green Strap w/ Deployant - $7,750

Zenith Defy Skyline Chrono Silver - El Primero - Full Set 2024 - Integrated Bracelet & Green Strap w/ Deployant - $7,750

Zenith - 03.9500.3600/01.I001 · $7,750
This is a Zenith Defy Skyline Chronograph, featuring the El Primero 3600 movement that beats at 36,000 vph and drives a 1/10th-second chronograph hand. The watch has a 42mm stainless steel case and a silver dial with a 'Starry Sky' pattern.

  • Condition: Excellent
  • Movement: El Primero 3600, automatic chronograph
  • Frequency: 36,000 vph (5Hz)
  • Power reserve: 60 hours
Posted at
May 11, 2026, 11:46 AM
Active
View listing on r/WatchExchange
[WTS] Ultra Rare Zenith El Primero Tourbillon Chronograph in 18K White Gold - Just 50 Made - Collector Set

Ultra Rare Zenith El Primero Tourbillon Chronograph in 18K White Gold - Just 50 Made - Collector Set

Zenith - 65.1260.4005/21.C505 · $20,850
The Zenith El Primero is a legendary chronograph featuring an incredible tourbillon and limited to just 50 pieces. The watch is housed in 18k white gold and features a beautiful black dial highlighting the tourbillon.

  • Condition: Really clean condition, minimal wear throughout
  • Case diameter: 45mm
  • Movement: El Primero automatic chronograph cal 4005
  • Strap material: Zenith black leather strap
Posted at
May 10, 2026, 11:09 PM
Active
View listing on r/WatchExchange
[WTS] Zenith Tipo CP-2 Chronograph 03.2240.4069, Underrated El Primero Beast (641/1000)

Zenith Tipo CP-2 Chronograph 03.2240.4069, Underrated El Primero Beast (641/1000)

Zenith - 03.2240.4069 · $4,150
Inspired by original Cairelli-issued military chronographs, this Zenith Tipo CP-2 Chronograph features a strong vintage tool watch character with a matte black dial and bold lume markers.

  • Condition: great, with light signs of normal wear
  • Case size: 43mm diameter
  • Movement: Zenith El Primero automatic chronograph (Cal. 4069)
  • Water resistance: 100m depth rating
Posted at
May 8, 2026, 8:40 PM
Active
View listing on r/WatchExchange
[WTS] Zenith Chronomaster. El Primero. Power Reserve. Open Heart. OEM Strap, OEM Deployant Clasp...

Zenith Chronomaster. El Primero. Power Reserve. Open Heart. OEM Strap, OEM Deployant Clasp...

Zenith - Chronomaster El Primero Power Reserve Open Heart · $3,400
A Zenith Chronomaster with El Primero movement and Power Reserve, featuring an Open Heart design.

Posted at
May 8, 2026, 5:24 PM
Active
View listing on r/WatchExchange