Strap for Constellation Co-Axial 27 Brushed Stainless Steel / Red Gold / Brown MOP

The lug width of model 123.20.27.20.57.001 measures 18 mm. This dimension is inherently consistent with the 27.30 mm case diameter and ensures harmonious visual proportions. To measure correctly, position a digital caliper between the inner shoulders of the two lugs, excluding the outer edges.

Alligator is the classic and most harmonious choice: the diamond-pattern texture creates a fascinating material contrast with the polished dial, and the natural color (brown, black, burgundy) perfectly complements the rose gold case. The elegant alternative is vegetable-tanned calf leather, which develops patina over time and adds chromatic depth.

Remove the watch from your wrist and use a spring bar tool (a small hook-shaped tool) to gently compress the spring of the lug attachment, then slide the spring bar out of the lug hole. Repeat on the other side. Insert the new strap following the reverse procedure, ensuring that the spring bars are fully inserted and locked in the lug holes.

Yes, any artisanal strap correctly calibrated to 18 mm width is mechanically compatible. Verify that the strap thickness is appropriate (typically 4-5 mm for this class of watches) and that the spring bars are standard ones. Milano Straps straps are made to the specifications of the lug width to ensure a precise fit.

A quality alligator or calf leather strap, worn daily, has an average lifespan of 2-4 years before requiring replacement, depending on climate humidity and perspiration. Vegetable tanning slows wear. Rubber or NATO straps have superior durability (5+ years). Storing the watch in a dry environment and periodically cleaning the strap with a soft cloth significantly extends its service life.