Strap for Speedmaster Broad Arrow Stainless Steel / Diamond / MOP

The lug width of the 3855.75.12 is 20mm. This width is the standard for sports chronographs of this caliber and is measured between the two case lugs. It is important to verify this measurement before purchasing an aftermarket strap to ensure perfect compatibility.

For this chronograph we recommend straps in black alligator or brown vegetable-tanned leather, which respect the aviator and sports identity of the model. Alligator offers elegance and durability, while vegetable-tanned leather develops a natural patina over time. For more technical uses, black rubber or a heavy canvas NATO are excellent choices.

Strap replacement is performed using the spring bars located on both sides of the case. Use a dedicated tool or spring bar tool to depress the spring and remove the bar, then separate the previous strap. Insert the new strap aligning it perfectly with the two 20mm lugs, then reinsert the bar until it clicks into place.

Yes, provided the strap is compatible with the 20mm lug width. Milanostraps offers a complete collection of straps in various materials (leather, alligator, rubber, fabric) all available for this width. We recommend choosing quality materials to ensure longevity and aesthetics consistent with the value of the watch.

The lifespan of a leather strap depends on usage and material. Naturally vegetable-tanned leather ages beautifully and can last 3-5 years with ordinary care, developing a characteristic patina. Alligator and shell cordovan are more durable, often exceeding 5-7 years. Rubber has even greater durability, ideal for those who desire a robust and water-resistant strap.