Zenith · El Primero

Strap for El Primero Chronomaster 42 Stainless Steel / Rose Gold / Silver / Alligator

Takes 21 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width21 mm
Case diameter42 mm
Reference51.2080.400/69.C494
FamilyEl Primero
MovementZenith caliber El Primero 400B hours, minutes, small seconds | date | Chronograph, column wheel
Year2017 - 2021
CaseRose Gold, Stainless Steel

Spring bar

Swiss Standard universal spring bars

The right category for this model · 316L steel, all lug widths 13–26 mm

Straps for the El Primero 51.2080.400/69.C494

Selected for the 21 mm lug width · workshop selection

All 21 mm straps →

The El Primero 51.2080.400/69.C494, seen from the bench

The Zenith El Primero Chronomaster 51.2080.400/69.C494 is a modern evolution of the 1969 automatic chronograph icon with central column and 10 Hz frequency. This bicolor 42mm case combines rose gold 18K and stainless steel, housing the rapid El Primero 400B caliber. The 21mm lug width accommodates specific straps; the movement features hours, minutes, chronograph with counter and tachymeter scale, plus date function. A sapphire exhibition caseback reveals the central column mechanism that measures tenths of seconds with exceptional precision.

Frequently asked questions

What is the lug width of the Zenith El Primero 51.2080.400/69.C494?

The lug width is 21mm. This measurement refers to the distance between the inner lugs and ensures precise compatibility with straps designed for this specific model. It is essential not to confuse this dimension with the case diameter (42mm).

Which strap material is recommended for the El Primero 51.2080.400/69.C494?

Alligator is the ideal choice: the scale texture dialogues elegantly with the chronograph's complexity, and the leather's mechanical resistance is superior to calf. Alternatively, shell cordovan offers exceptional hardness and vertical grain that resists scratches; vegetable-tanned calf is perfect for those seeking sobriety and natural patina development over time.

How do I change the strap on the Zenith El Primero 51.2080.400/69.C494?

Use a spring bar tool or flat screwdriver to compress the attachment pins (spring bars) positioned horizontally between the lugs. Gently lift the worn strap until the pin slides free from the seats. Insert the new strap by aligning the pins to the same positions and release slowly. Verify that both pins are firmly seated before wearing the watch.

Which aftermarket straps are compatible with the Zenith 51.2080.400/69.C494?

Any strap manufactured for 21mm lugs is compatible with this model. MilanoStraps offers a wide selection of straps in alligator, calf, shell cordovan, and technical rubber, all customisable in length, initials, and stitching colour. Artisanal quality ensures the strap integrates perfectly without any play.

What is the average lifespan of a leather strap on a wristwatch like the El Primero?

A quality artisanal alligator strap lasts an average of 3-5 years with moderate daily use. Shell cordovan, being denser, can last 6-8 years. Vegetable-tanned calf tends to show visible wear (creases, cracking) after 2-4 years, but the patina it develops is part of its appeal. Durability depends on climate, frequency of use, and leather maintenance.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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Casati Milano · Via XX Settembre 15, Milan · by appointment only