Strap for Seamaster Master Co-Axial 39.5 Olympic Timekeeper Stainless Steel / White / Red

The lug width of the Seamaster 522.32.40.20.04.004 is 20 mm. This width is specific to the model and is determined by the internal distance between the two lugs of the case. A strap of smaller or larger width will not fit correctly. To measure your lug width precisely, remove the current strap and use a digital caliper to measure perpendicularly between the lugs, excluding the curvature edges.

For the 39.50 mm steel Seamaster 522, we recommend a high-quality alligator strap with medium grain, dark brown, black, or cognac color. Alternatively, an aged shell cordovan offers sophisticated elegance, while an FKM rubber strap keeps the watch in pure sports context. For formal occasions, a smooth calf leather in dark tone creates sharp contrast with the satin-finished steel. Ballistic nylon NATO straps guarantee daily practicality and reversibility.

The Seamaster 522 uses a spring bar lug system (Omega Lug design). To remove the original strap: position the watch on a soft pad, locate the small protruding pin beneath the crown-side lug, use a spring bar tool (specific tool) to gently push the pin downward and, simultaneously, extract the lug. Repeat on the other side. To fit the new 20 mm strap, reverse the procedure, ensuring the pin inserts correctly into the groove of the new strap's lug. If you prefer to avoid DIY, the Casati Milano atelier offers professional strap change service.

Any strap with 20 mm lug width is compatible with the Seamaster 522.32.40.20.04.004. Online you will find a complete selection of 20 mm straps in alligator leather, calf, shell cordovan, rubber, and fabric. Always verify that the strap specifies 20 mm width and that the ends are rounded or slightly tapered to fit the Omega case lugs. Higher quality straps include an internal groove that facilitates spring bar placement.

A quality leather strap, worn moderately and subjected to regular maintenance, has an average durability of 3–5 years. Premium materials such as alligator and shell cordovan tend to last longer thanks to their dense fiber. Durability depends on use: daily wear accelerates aging compared to occasional wear. To extend the life of the strap, avoid prolonged exposure to moisture and perspiration, dry it after use, and apply a protective balm every 6–12 months. The Casati Milano atelier guarantees 18 months on custom-made straps.