Strap for Seamaster Master Co-Axial 39.5 Olympic Timekeeper Stainless Steel / Black / Blue

The lug width of the Omega Seamaster 522.32.40.20.01.001 is 20 millimetres. This dimension is determined by the geometry of the 39.50mm case and represents the distance between the two lateral lugs of the case. It is essential to verify this measurement before ordering an aftermarket strap, as an incompatible lug width cannot be installed correctly without damaging the watch.

For a Seamaster with a marine vocation, we recommend three main options: 1) Dark brown or havana alligator for formal elegance, with natural patina over time; 2) Vegetable-tanned calf leather for a raw and contemporary texture, ideal for daily wear; 3) Satin or natural vulcanised rubber for diving and saltwater use. The blue dial pairs particularly well with straps in dark brown, charcoal black or slate blue shades.

The strap should be removed using a specific tool (spring bar remover) that allows you to extract the fixing pins from the lugs without scratching the case. Position the tool under the spring bar, apply gentle upward pressure, and extract the pin. It is possible to do this yourself with care, or entrust the operation to a qualified watchmaker. Once the new strap is installed, it is essential to verify that the pins are inserted symmetrically and that the strap is aligned with the case before fully tightening.

Yes, provided the lug width is exactly 20 millimetres. Aftermarket straps—particularly those handcrafted with folding steel <a href="https://milanostraps.it/pages/termine-glossario/deployante">deployante</a> clasps—are perfectly compatible with the Seamaster 522.32.40.20.01.001 and do not affect the warranty if installed correctly. It is advisable to choose manufacturers who respect manufacturing tolerances (±0.5mm) to avoid settling or mechanical play during use.

A quality leather strap (alligator or calf) lasts on average 3-5 years with daily use, even on a watch with a marine vocation, provided it is removed before prolonged saltwater immersion and dried carefully after each contact with moisture. Leather with vegetable tanning is more resistant to fresh water, but remains sensitive to prolonged salt exposure. For those who regularly dive, it is advisable to alternate between leather and rubber straps, or choose natural vulcanised rubber to ensure a lifespan of 7-10 years or more.