Strap for Seamaster Diver 300M Master Co-Axial 42 Stainless Steel / Green / Rubber

The lug width is 20mm. This measurement is specific to this reference and must be measured with a digital caliper between the lateral lugs of the case. Do not confuse it with the case diameter (42mm): the lug width is the only relevant dimension for purchasing compatible straps.

It depends on use. For frequent diving: FKM or nitrile rubber dry quickly. For daily elegance: polished black alligator or vegetable-tanned calf develop patina over time. For tactical versatility: cotton NATO strap with reinforced edges. For those alternating sport and formality: cognac brown shell cordovan offers water resistance and aesthetic richness.

The Seamaster 210.32.42.20.10.001 uses standard 1.2mm diameter spring bars. With a spring bar remover, gently push down one spring bar to disengage them from the lateral lugs. Insert the new strap by aligning the passants to the lug holes, then re-engage the spring bars until you feel the click. If you are not experienced, Casati Milano performs the change by appointment.

Yes, provided the lug width is exactly 20mm. Artisanal compatible straps by Milano Straps are constructed with precise tolerances to ensure perfect fit. Avoid generic straps from online platforms, which often feature inadequate construction tolerances and poor-quality materials.

Durability depends on material and use. Alligator with vegetable tanning resists 3-5 years of daily use in dry environments; vegetable-tanned calf 2-3 years if regularly exposed to humidity. Shell cordovan, thanks to its greater density, lasts over 5 years. FKM rubber resists beyond 7 years. Casati Milano offers an 18-month warranty on all artisanal straps and repairs or replaces them for wear.