Strap for Speedmaster Broad Arrow 44.25 Stainless Steel / Silver Stripes

The lug width of the 321.13.44.50.02.001 is exactly 21 mm. It is essential to verify this dimension with precision (using a digital caliper) before ordering a strap, as undersized straps create irregular lugs and compromise the anchorage to the spring bars.

Natural alligator (niloticus) with soft patina is the noblest choice, as the fine grain does not compete with the severity of the brushed steel case. An excellent alternative is vegetable-tanned calf leather for those who prefer visible aging. High-density synthetic rubber is ideal for intensive use while maintaining formal wearability.

Use a spring bar tool (specific tool for the spring bars) by inserting the flat tab into the appropriate groove of the spring bar and gently pushing inward to compress the spring. Remove the spring bar when fully compressed, then detach the strap. Proceed in reverse to install the new 21 mm strap, ensuring the spring bar is correctly aligned in both lugs.

Yes, provided that the strap is specific to 21 mm lug width. Any artisanal 21 mm strap is perfectly compatible: alligator, calf, rubber, suede. We recommend a titanium or steel deployant clasp to distribute the load of the volumetric case in a balanced manner.

A quality leather strap (alligator or vegetable-tanned calf) lasts an average of 3-5 years with moderate daily use. Longevity depends on exposure to humidity, direct sunlight, and cleaning frequency. Natural alligator ages elegantly and can remain functional beyond 5 years. Casati Milano's warranty covers 18 months against manufacturing defects.