Strap for Speedmaster Professional Moonwatch Alaska Project

The lug width of the Speedmaster Moonwatch 311.32.42.30.04.001 is 20mm. This dimension is the attachment point between the case and the strap, measured as the external distance between the lugs. Using a strap of different size (18mm or 22mm) would compromise the fit and original design. Always verify with a digital caliper by measuring between the inner lug attachments.

It depends on intended use and desired aesthetics. To maintain historical authenticity: dark coffee shell cordovan with natural patina. For everyday versatility: vegetable-tanned calf with double stitching. For sophisticated elegance: matte black alligator. For instrumental vocation: taupe grey or navy blue NATO. Each material offers different tactile characteristics and aging properties.

Strap replacement requires removing the spring bars (pins) from the lugs. Use a dedicated tool (spring bar removal tool) or a small screwdriver to gently push the pin inward, freeing the old strap. Insert the new strap by aligning the lug hole with the lug hole opening, then reinsert the pin until it clicks into position. The operation is reversible with no permanent damage if performed carefully.

Yes, any strap with 20mm lug width is compatible. You will find options from specialized manufacturers on the market: full grain leather, FKM rubber, NATO fabric, shell cordovan, vintage calf. Verify that the strap has an appropriate central lug hole and that the thickness is consistent with the case profile (not too thick to avoid binding at the lugs). MilanoStraps offers a curated selection of 20mm options with customization.

Durability depends on the tanning method and usage. A shell cordovan with natural vegetable tanning resists 3-5 years of daily wear with regular maintenance (gentle cleaning, summer conditioning). A vegetable-tanned calf strap varies 2-4 years depending on humidity exposure. FKM rubber straps last 4-6 years with minimal maintenance. Aging is not a defect but an aesthetic characteristic: natural patina is a sign of authenticity. Casati Milano offers an 18-month guarantee on each creation.