Strap for Montbillant 38 Stainless Steel / Copperhead Bronze / Japan Special Edition

The Breitling Montbrillant A4137012/Q609/223A requires straps with a lug width of 20mm. This measurement refers to the internal distance between the two lugs of the case, best verified with a digital calliper at the point of strap attachment. Using the correct width ensures a precise fit with no lateral play.

For the Montbrillant A4137012/Q609/223A with its stainless steel case and black dial, the most suitable options are: smooth alligator in black or midnight blue for formal settings, vegetable-tanned calf leather in cognac tones for a classic-casual register, vulcanised rubber for sports use, and technical nylon NATO for an aeronautical aesthetic consistent with Breitling's heritage. The correct width is 20mm.

To replace the strap on the Montbrillant A4137012/Q609/223A, a fine-tipped spring bar tool is required. The spring bars are compressed via the lateral groove of each lug, releasing the strap from the case. It is advisable to work on a soft surface to prevent scratches to the stainless steel case. If in doubt, consult a watchmaker or the Casati Milano atelier.

Yes, the Breitling Montbrillant A4137012/Q609/223A uses standard 20mm lugs, compatible with a wide range of quality aftermarket straps. MilanoStraps offers handcrafted straps in alligator, calf leather, shell cordovan and NATO, made specifically for this lug width, ensuring precise fitment and manufacture-level finishing.

The lifespan of a leather strap depends on the material and care routine: a quality vegetable-tanned calf strap typically lasts 2–4 years with daily wear, developing a personal patina over time. Alligator or shell cordovan, due to their denser fibre structure, can last 5–8 years or more with proper maintenance. Prolonged exposure to water and UV light should be avoided to maximise longevity.