Omega · Speedmaster Moonwatch

Strap for Speedmaster Broad Arrow

Takes 19 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width19 mm
Case diameter39 mm
ReferenceCK2915-2
FamilySpeedmaster Moonwatch
MovementOmega caliber 321 small seconds, hours, minutes | Chronograph, column wheel
Year1958 - 1959/6
CaseStainless Steel

Recommended spring bar

Spring bars Omega Speedmaster Seamaster 19mm

Technical match for lug width and diameter · lug 19 mm · Ø 1.8 mm

All Omega spring barsOpen →

Straps for the Speedmaster Moonwatch CK2915-2

Selected for the 19 mm lug width

All 19 mm straps →

The Speedmaster Moonwatch CK2915-2, seen from the bench

The Speedmaster Moonwatch CK2915-2 represents one of the first versions of the famous Omega chronograph. The movement is the manual-winding caliber 321 with column-wheel chronograph function, hours, minutes, small seconds. The lugs measure 19mm in width.

Frequently asked questions

What is the lug width of the Omega Speedmaster Moonwatch CK2915-2?

The lug width of the CK2915-2 is 19 millimetres. This dimension is fixed and determined by the geometry of the three-piece case, where the lugs are machined from the central body. It is not possible to use straps of different widths without compromising the mechanical fit and final aesthetics.

What is the best strap material for the Omega Speedmaster Moonwatch CK2915-2?

Alligator represents the most coherent aesthetic choice: the linear texture of the leather reflects the minimalist design of the instrument and develops an authentic patina over time. A valid alternative is technical fabric NATO, which maintains the historical backup function and resists any environmental stress. Calf leather offers tactile softness, and vulcanised rubber is ideal for hot and humid climates.

How do you change the strap on an Omega Speedmaster Moonwatch CK2915-2?

The CK2915-2 is fitted with a strap via the case lugs, which are secured by spring bars. It is necessary to remove the bars with a dedicated tool (spring bar tool) by applying calibrated inward pressure. Once the lugs are freed, the strap slides off. To fit the new strap, align the lug hole with the case hole, insert the spring bar and ensure that both ends of the spring snap into position. If you are not experienced, consult a professional watchmaker to avoid damage to the case.

Is it possible to use aftermarket compatible straps on the CK2915-2?

Yes, all straps with a lug width of 19 millimetres are mechanically compatible. However, construction quality varies significantly. Low-end straps use synthetic or printed leathers that degrade rapidly. For a watch of this historical importance, it is advisable to choose straps made from natural materials—alligator, calf, shell cordovan—and with hand-stitching that guarantees longevity and aesthetic quality over time.

How long does a leather strap last on an Omega Speedmaster Moonwatch CK2915-2?

Durability depends on the material chosen and usage. Professional-grade alligator lasts 5-7 years with regular maintenance (annual cleaning and conditioning). Calf leather, being less structured, tends to give way at flex points after 3-4 years, especially if exposed to frequent moisture. Shell cordovan, if available, lasts 10 years or more thanks to the natural density of the fibre. Technical fabric NATO lasts indefinitely if washed periodically. Maintenance (cleaning, protection from direct impact) significantly extends the useful life of any strap.

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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