Omega · Constellation
Strap for Constellation Co-Axial 35 Stainless Steel / Diamond / Blue Supernova / Alligator
Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.
Lug width
Straps for the Constellation 123.18.35.20.56.001 (aka: 12318352056001)
Selected for the 20 mm lug width · workshop selection
Black Alligator Strap with Light Blue Edges€149
Red Alligator Strap Water Resistant€195
Green Rubberized Alligator Strap with Ecru Tribal Stitching€149
Hammered Calfskin Strap Light Blue€98
Vintage Olive Green Calf Leather Watch Strap€80
The Constellation 123.18.35.20.56.001 (aka: 12318352056001), seen from the bench
Frequently asked questions
What is the lug width of the Omega Constellation 123.18.35.20.56.001?
The lug width is 20mm. This dimension is specific to the model and ensures optimal proportions between the 35mm case and the wrist. For accurate measurement, position the ruler in the natural V between the lugs, starting from the inside of one and reaching the inside of the other, passing over the bottom of the case.
Which strap should I choose for the Constellation 123.18.35.20.56.001?
For this model we recommend premium alligator (natural grain texture), vegetable-tanned calf for a patina that ages nobly, or shell cordovan for legendary durability. The 20mm handcrafted straps from milanostraps.it are customizable in leather, color and stitching. The Casati Milano atelier offers bespoke made-to-measure solutions with direct consultation.
How do I change the strap on the Omega Constellation 123.18.35.20.56.001?
The Constellation's lugs are fitted with spring bars that should be removed gently with the appropriate tool (spring bar tool). Insert the tip into the space between the lug and the spring bar, apply slight pressure to release the internal spring, and slide the spring bar outward. The process is reversible and requires no jeweler intervention.
Are aftermarket straps compatible with the Constellation 123.18.35.20.56.001?
Yes, provided the lug width is exactly 20mm. The handcrafted straps from milanostraps.it are made to this specific width and guarantee mechanical compatibility. Always verify that the lug depth (approximately 2.5mm) is respected by the manufacturer to avoid lateral play.
How long does a leather strap last on a watch worn daily?
A handcrafted alligator or vegetable-tanned calf strap lasts on average 3-5 years with daily use and regular maintenance (cleaning with a damp cloth, occasional conditioning). Shell cordovan is more durable, lasting over 7 years. Casati Milano straps come with an 18-month warranty and can be regenerated at the atelier with minimal investment.
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.
Request an appointment →Casati Milano · Via XX Settembre 15, Milan · by appointment only

