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

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

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

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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

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