Omega · Speedmaster Moonwatch
Strap for Speedmaster Professional Moonwatch Chocolate / Bracelet
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 Speedmaster Moonwatch 311.30.42.30.13.001 (aka: 31130423013001)
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 Speedmaster Moonwatch 311.30.42.30.13.001 (aka: 31130423013001), seen from the bench
Frequently asked questions
What is the exact lug width of the Speedmaster Moonwatch 311.30.42.30.13.001?
The lug width of this model is 20 mm. This measurement is obtained by positioning a caliper from the inside of one lug to the inside of the other, excluding the thickness of the lugs. Precise measurement is essential for purchasing a compatible strap without trimming or mechanical forcing.
What strap do you recommend for the Omega Speedmaster 311.30.42.30.13.001?
It depends on use and aesthetic preference. Aged grey alligator harmonizes the sobriety of stainless steel; full-grain calf in medium brown creates controlled contrast; dark Shell Cordovan absorbs light and creates monochromatic effect. Black Tropic rubber is ideal for marine environments; grey military cordura NATO strap restores the chronograph's civil identity.
How do you change the strap on a Speedmaster Moonwatch?
Three tools are required: a strap knife, a replacement spring bar for each lug, and a well-lit work space. Position the watch horizontally, insert the knife between the strap and the lug to push the spring bar outward, remove the old strap, align the new spring bar with its seat, insert the new strap and push it until the mechanical click. Avoid forcing beyond the tactile locking signal.
Is an aftermarket strap compatible with the 311.30.42.30.13.001?
Yes, provided it respects the 20 mm lug width. Customizable handcrafted straps from Milan Straps are designed for this measurement and guarantee smooth passage through the lugs without mechanical defects. Atelier Casati Milano also creates made-to-measure straps with personal choice of leathers and 18-month warranty.
How long does a leather strap last on a watch like the Speedmaster?
A quality leather strap, subjected to vegetable tanning, develops a natural patina in the first 12-18 months and maintains structural integrity for 5-7 years of daily wear. Deterioration depends on frequency of wear, water exposure, climate humidity and preventive care. A vegetable-tanned strap ages in a controlled and predictable manner; wear becomes aesthetic and increases the narrative value of the object.
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

