Strap for Speedmaster 57 Co-Axial Yellow Gold / Silver / Bracelet

The lug width of the Speedmaster '57 (ref. 331.50.42.51.02.001) is 20 mm. This width is standard for this model and ensures balanced proportions with the 41.50 mm case diameter. It is essential to verify precisely that the strap measures exactly 20 mm (tolerance 19.8–20.2 mm) to avoid insertion issues in the lugs and premature case wear.

For the Omega Speedmaster '57 in yellow gold, cognac alligator represents the most refined choice: the longitudinal grain dialogue with the patina of gold, creating an aesthetic continuum. Vegetable-tanned calf is an elegant and durable alternative that evolves over time. Shell cordovan offers an almost glazed surface with intrinsic hardness, ideal for a sophisticated style. For those seeking pure sportiness, the canvas NATO remains the authentic choice.

To change the strap: 1) Obtain a high-quality spring bar tool, not improvised. 2) Place the watch on a soft surface (rubber mouse pad). 3) Locate the small hole in the lug passage and push the pin downward with the tool tip until you hear the disengagement "click". 4) Extract the pin from the lug. 5) Repeat on the other side. 6) Insert the new strap and push the pins until they snap into place. If unsure, entrust the operation to Casati Milano: the atelier offers professional strap replacement with warranty.

Yes, any 20 mm strap is dimensionally compatible with the Speedmaster '57. On milanostraps.it you will find a collection of 20 mm handcrafted straps made from premium leather (alligator, calf, shell cordovan). The straps are available customizable in length, color, initials and stitching thread, ensuring complete compatibility and construction quality superior to OEM straps.

The durability of a leather strap depends on use, climate and material: alligator typically lasts 5–7 years with regular use; vegetable-tanned calf 4–6 years (but improves aesthetically over time); shell cordovan 6–8 years thanks to intrinsic hardness. Humidity, sweat and sun exposure accelerate aging. Casati Milano guarantees 18 months on custom-made straps, with the possibility of aesthetic regeneration through specific treatments.