Strap for Speedmaster Broad Arrow Stainless Steel / Diamond / MOP / Bracelet

The Broad Arrow 3555.75.00 features a lug width of 20 millimetres. This dimension is critical for sourcing compatible straps and does not tolerate variations to 18 or 22mm. Measurement should be taken from inside to inside of the horizontal pins using a digital caliper or flexible ruler.

Vegetable-tanned alligator represents the most conservative and harmonious choice with the instrument aesthetic, particularly in dark shades. Calf leather offers greater versatility and dynamic colour aging. Technical fabric NATO provides sporting chronograph character, while synthetic rubber ensures practicality in humid environments or for those preferring minimal maintenance.

Replacement requires a spring bar tool to remove the horizontal pins from the lugs. Insert the flat blade of the tool into the lateral slot of the pin, gently push inward to engage internal spring pressure, then extract the pin. Repeat on the other side. Thread the new strap by aligning its lug to the holes and reinsert the pins until the spring clicks. Verify stability by gently pulling the strap.

The 20mm dimension is shared by numerous medium and large Omega models; however, compatibility does not imply aesthetic coherence. A 20mm strap will physically mount on any watch with 20mm lugs, but visual proportion depends on case diameter. The Broad Arrow 3555.75.00 was proportioned around 42mm and chronograph mechanics, therefore straps designed for this reference maximise harmony.

Longevity depends on material, tanning method, and daily use. High-quality vegetable-tanned alligator maintains structural integrity between 4 and 7 years with regular wear (5-6 days weekly). Calf leather, given its thinner gauge, exhibits slightly reduced durability (3-6 years). Synthetic rubber, whilst suffering less from climatic factors, tends to become brittle after 5-6 years. The Casati Milano warranty covers 18 months from manufacturing.