Strap for Chronomat 40 GMT Six Nations Ireland

The lug width of the Breitling Chronomat 40 GMT A323987B1L1A1 is 20 mm. This measurement refers to the internal distance between the lower lugs of the case, where the springbar securing the strap is inserted. It is a widely standardised size in high-end sports watchmaking.

For the Chronomat 40 GMT A323987B1L1A1 in stainless steel, the most coherent choices with the instrument's DNA are: alligator belly in black or brown for a formal register, shell cordovan for those seeking character and patina over time, vulcanised rubber for sporting use and full water resistance, or vegetable-tanned leather for a balance between elegance and everyday versatility. The 20 mm size ensures maximum availability of aftermarket and handcrafted options.

To replace the strap on the Chronomat 40 GMT, you will need a springbar tool — a double-tipped instrument with fine points. Insert the tip into the dedicated slot or between the lug and the springbar to compress the retaining spring and release the strap. Care should be taken not to scratch the stainless steel case: it is advisable to protect the lugs with a soft cloth or masking tape before proceeding.

Yes, the Chronomat 40 GMT A323987B1L1A1 uses standard 20 mm springbars, compatible with the wide range of aftermarket straps available on the market. Milanostraps.it offers a selection of handcrafted straps in 20 mm — in leather, rubber and NATO — designed to fit the specific geometry of Breitling's lugs, including the lower lug curvature.

The lifespan of a leather strap depends on the type of hide, maintenance and intensity of use. A quality alligator strap, worn daily, typically lasts between 2 and 4 years before showing signs of structural wear. Shell cordovan, thanks to the density of its fibres, tends to last longer whilst developing a distinguished patina. Regular conditioning with leather cream and alternating between straps will significantly extend the life of the leather.