Strap for Seamaster Aqua Terra 150m Master Co-Axial 38.5 Stainless Steel / Red Gold / Silver / Bracelet

The lug width is exactly 20 millimeters. To verify it, measure the internal distance between the two lugs: it must be 20mm. This dimension is standard for all Aqua Terra 231.20.39.21.02.001 regardless of the production year.

Louisiana alligator in vegetable tanning is the choice of maximum aesthetic impact: the natural grain and reflectance enhance the warm yellow of rose gold and create a fascinating contrast with the teak dial. Vegetable-tanned calf offers a more conservative alternative with long durability and patina that develops over time.

Use a spring bar tool to remove the spring bars from the lugs. Insert the tip of the tool into the small hole along the lug and push downward to disengage the spring bar. Repeat for both sides. The reverse procedure assembles the new 20mm strap. Avoid forcing to prevent damage to the lugs.

Yes, any 20mm strap is geometrically compatible with standard Omega spring bars. We recommend verifying that the strap has appropriate lug thickness (approximately 3mm) to avoid excessive play. Milano Straps 20mm straps are all tested for this reference.

A quality leather strap (alligator, calf, cordovan) in vegetable tanning lasts 24-36 months with daily use, longer if alternated with other straps. FKM rubber guarantees 4+ years. Durability depends on exposure to sweat, fresh water, and extreme temperatures. Casati Milano offers an 18-month warranty on all custom straps.