Strap for Seamaster Aqua Terra 150M Co-Axial 38.5 Stainless Steel / Yellow Gold / Diamond / Black / Bracelet

The lug width of the 231.25.39.21.51.002 model is 20mm. This measurement is determined by the distance between the inner edges of the case lugs and is essential to ensure compatibility and optimal strap fit.

For this two-tone model, dark brown alligator with steel deployment clasp represents the most coherent choice, creating visual continuity with the yellow gold and maintaining sportive elegance. Valid alternatives include aged cognac calf or navy rubber for more dynamic contexts.

The strap is replaced using a spring bar remover to remove the spring bars that secure the strap to the lugs. Position the small tool under the spring bar, gently lift until the pin retracts, and slide the strap outward. The reverse process secures the new strap.

Any strap made for 20mm lug width is compatible with this model. You can browse the complete 20mm strap collection on milanostraps.it, where you will find premium leathers, customizable finishes and bespoke options made by the Casati Milano atelier.

The lifespan of a leather strap varies based on usage and leather quality. On average, an alligator or calf strap of quality lasts 3-5 years with daily wear, developing a natural patina over time. The Casati Milano atelier offers an 18-month warranty on all custom-made straps.