Zenith El Primero El Primero Chronomaster Full Open 42 Stainless Steel / Alligator
Reference 03.2081.400/78.C813
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 Defy Classic Aero Chronograph El Primero 46mm - Custom 3D printed Bezels $1,999](https://preview.redd.it/z2zi25lqplif1.png?width=640&crop=smart&auto=webp&s=cb137edd657cc0a1d436d8125bd3a8a81319acb4)
Zenith Defy Classic Aero Chronograph El Primero 46mm - Custom 3D printed Bezels $1,999
A Zenith Defy Classic Aero Chronograph featuring the El Primero 4000 SC movement in a 46mm case. The watch has an aftermarket strap/buckle and multiple custom 3D-printed bezels.
- Condition: - Keeps excellent time, strong amplitude (~300). - Crystal, dial, and hands are in excellent shape. - Case sides and lugs show visible scratches (see video/photos)
- Case Size: 46mm
- Movement: Zenith Calibre El Primero 4000 SC
- Case Condition: visible scratches on sides and lugs

Zenith 42mm El Primero Chronomaster Open Heart Stainless Steel Complete
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

Zenith El Primero Synopsis Open Heart � BOX & PAPERS � 03.2170.4613/01.M2170
A Zenith El Primero Synopsis Open Heart watch with a 40-millimeter case diameter and gold-toned hands, featuring an open heart design and classic modern architecture.
- Condition: Excellent, little to no visible wear
- Case Diameter: 40mm
- Bracelet Length: 16.5 links
- Bracket Fit: up to 7.25 inches in circumference

Zenith Chronomaster - El Primero - Original - Tricolor Dial - Complete
A Zenith Chronomaster Original with a tricolor dial, featuring an automatic movement and stainless steel case.
- Condition: Excellent
- Case size: 38mm diameter

Zenith 42mm El Primero Chronomaster Open Heart Stainless Steel Complete
A Zenith El Primero Chronomaster Open Heart chronograph watch with a 42mm stainless steel case, featuring a Caliber Zenith El Primero 4061 movement and a date of manufacture in October 2014.
- Condition: Mint Condition
- Case diameter: 42mm
- Movement frequency: 36,000 VPH

Zenith 42mm El Primero Chronomaster Open Heart Stainless Steel Complete
This is a Zenith El Primero Chronomaster Open Heart chronograph watch, featuring a 42mm stainless steel case and powered by the Caliber Zenith El Primero 4061 movement.
- Condition: Mint Condition with light hairline scratches
- Case diameter: 42mm
- Movement frequency: 36,000 VPH
- Power reserve: 50 hour PR
Zenith Class Sport El Primero Chronograph Black Dial Hand Wound 02.0500.420
This Zenith Class Sport El Primero Chronograph is a hand-wound mechanical watch with a black dial and stainless steel case.
- Condition: 95%
- Size: 39mm diameter
- Function: Chronograph ; date

Zenith Grande Class Open El Primero Chrono Power Reserve 03.0520.4021, Black B&P
This Zenith Grande Class Open El Primero Chronograph features an in-house movement, chronograph function, power reserve indicator, and is water resistant to 50m.
- Condition: Good condition, some wear on the strap and a small blemish on the sapphire crystal
- Movement: Automatic, in-house Zenith 4021H
- Base movement: Zenith El Primero 400
- Alternations per hour: 36,000

ZENITH CHRONOMASTER SPORT El PRIMERO YOSHIDA GREEN DIAL LIMITED EDITION 2024
The Zenith Chronomaster Sport Yoshida 'Hulk Edition' features a stainless steel case with a green ceramic bezel and dial, powered by the El Primero Caliber 3600.
- Condition: Mint, Unpolished Condition
- Limited edition: 1 of 244 pieces
- Case material: stainless steel
- Bracelet material: stainless steel