Omega · Constellation

Strap for Constellation Co-Axial 38 Stainless Steel / Red Gold / Diamond / Brown

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter38 mm
Reference123.25.38.21.63.001 (aka: 12325382163001)
FamilyConstellation
MovementOmega caliber 8500 hours, minutes, seconds | date | chronometer, co-Axial escapement
CaseRed Gold, Stainless Steel

Recommended spring bar

Spring bars Omega 20mm — 1.8mm diameter

Technical match for lug width and diameter · lug 20 mm · Ø 1.8 mm

All Omega spring barsOpen →

Straps for the Constellation 123.25.38.21.63.001 (aka: 12325382163001)

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The Constellation 123.25.38.21.63.001 (aka: 12325382163001), seen from the bench

The Omega Constellation reference 123.25.38.21.63.001 is equipped with the automatic caliber 8500 with Co-Axial escapement and chronometer certification. The movement offers indication of hours, minutes, central seconds and date. The Constellation series represents one of the historical collections of the Swiss brand, characterized by precision and technical reliability.

Frequently asked questions

What is the lug width of the Omega Constellation 123.25.38.21.63.001?

The lug width is 20mm. This measurement indicates the distance between the two attachment pins on the case. It is the fundamental parameter for selecting compatible straps. You can verify it with a digital caliper by measuring between the two lateral attachments at 12 o'clock and 6 o'clock on the case.

Which strap is best for the Constellation 123.25.38.21.63.001?

It depends on the context of use. Black alligator or tobacco brown is the reference choice for formal elegance, enhancing the refined design of the two-tone case. Vegetable-tanned calf leather offers greater versatility and develops a highly personal patina over time. Shell cordovan guarantees superior durability and a vintage-contemporary aesthetic. NATO remains ideal for those seeking everyday dynamism.

How do you change the strap on an Omega Constellation?

The operation requires specific tools: a spring bar removal tool or dedicated pin tool. Place the watch with the pins facing upward, locate the small depression on one of the lateral pins, insert the tool and press gently to extract the pin. Repeat for the other side. Some artisanal straps feature leather loops that facilitate removal without tools. If you are not experienced, entrust the task to a professional watchmaker or contact Casati Milano atelier for technical support.

Does the Constellation 123.25.38.21.63.001 accept aftermarket straps?

Yes, absolutely. The 20mm lug width is standard on many artisanal and industrial straps. Verify that the strap is specifically designed for 20mm lug width and that the attachments are curved, a feature that promotes adherence to the case. On milanostraps.it you will find catalogs dedicated to compatible 20mm straps, customizable in leather, color and stitch thread.

What is the average durability of a leather strap for the Omega Constellation?

A quality artisanal leather strap (alligator, calf, shell cordovan) lasts on average 2–4 years with daily wear, provided regular maintenance is performed. Prolonged exposure to water, intense heat and UV rays shortens the useful life. Vegetable-tanned calf straps and shell cordovan age magnificently, developing a patina that increases appeal. Casati Milano atelier applies an 18-month warranty on all custom straps, covering manufacturing defects and premature wear.

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