Strap for Speedmaster Professional Moonwatch 3861 Sedna Gold - Diamond / Brown / Bracelet

The lug width of reference 310.55.42.50.13.001 is exactly 20mm. This measurement represents the horizontal distance between the two attachment terminals on the case where the strap is inserted. Omega chose 20mm to maintain the correct proportions between the 42mm case and the strap, avoiding both the unbalanced effect and the oversized appearance that an oversized lug would have caused.

To enhance the nobility of Sedna Gold, alligator represents the most elegant choice thanks to its natural grain and the patina that develops over time. Italian calf tanned with vegetable tanning offers immediate softness and fascinating aging. Shell cordovan is ideal for those seeking extraordinary durability and an exclusive cognac patina. For sportive versatility, nato nylon or FKM rubber are legitimate alternatives that maintain the Moonwatch's chronographic DNA.

Remove the watch from your wrist and place it on a soft surface. Use a spring bar tool or thin screwdriver to push the spring bar pin (which passes through the lug and connects the strap to the case). Gently press on one side until the pin extracts completely. Repeat on the other side. Insert the new strap by aligning it with the slots, then reinsert the pin from the other side until it snaps into place. Verify that the strap is firmly secured before wearing the watch again.

Yes, any strap with a 20mm lug width is compatible with your Speedmaster Moonwatch, regardless of brand. It is important to verify that the width is exactly 20mm (not 19mm or 21mm, which will not fit correctly). We recommend straps made by artisans specializing in luxury watches, who respect the robustness and finishing standards required by a chronograph of this caliber.

Durability depends on the type of leather, frequency of use, and care. An alligator or shell cordovan strap, with quality tanning, can last 5-8 years of daily wear before requiring replacement. Italian calf tanned with vegetable tanning tends to show signs of wear more quickly (3-5 years), but develops a fascinating patina. The natural aging of leather is part of the strap's beauty, not a flaw. To extend its life, avoid prolonged water exposure and allow the leather to breathe periodically by alternating with other straps.