Technical Archive

Breitling
Chronomat 40 GMT A32398A21L1A1— lug 20mm

Breitling Chronomat 40 GMT A32398A21L1A1: 20mm strap. Alligator, box calf, shell cordovan and rubber, cut and stitched in Milano. Choose your leather.

Chronomat 40 GMT Stainless Steel / Turquoise / Hong Kong

Artisanal Note

"This model requires a precise 20mm lug width to preserve the original sartorial balance."

Technical Specifications

Breitling A32398A21L1A1
Lug Width
20 mm

The essential strap measurement.

Browse 20mm straps →
Reference

A32398A21L1A1

Movement

Breitling caliber Caliber 32 Hours, Minutes, Seconds, Additional 24 Hour Hand (adjustable) | Date

The Heritage

The Chronomat GMT houses the Breitling 32 automatic caliber with hour, minute, second, adjustable GMT hand, and date functions. The watch features 20mm lugs and offers the ability to monitor a second time zone through the 24-hour hand. The reference A32398A21L1A1 represents a Chronomat variant with a GMT complication dedicated to travelers.

FAQ

What is the lug width of the Breitling Chronomat 40 GMT A32398A21L1A1?

The lug width of the Breitling Chronomat 40 GMT A32398A21L1A1 is 20mm. This measurement should be taken between the inner edges of the lugs, at the point where they meet the case, using a millimetre calliper to ensure accuracy before purchasing an aftermarket strap.

What is the best strap for the Breitling Chronomat 40 GMT?

For the Breitling Chronomat 40 GMT, a polished alligator leather strap or a shell cordovan strap in vegetable tanning are the options that best complement the watch's technical character and the interplay of brushed and polished steel surfaces. For sporting contexts, a technical nylon NATO strap or a vulcanised rubber strap provides robustness and comfort without compromising dial legibility.

How do you change the strap on a Breitling Chronomat 40 GMT?

To replace the strap on the Breitling Chronomat 40 GMT, you will need a springbar tool inserted into the lug slot to compress the spring bars securing the strap to the case. It is advisable to work on a soft surface to avoid scratching the brushed steel. If in doubt, a watchmaker or the Casati Milano atelier can carry out the swap in a matter of minutes.

Are there aftermarket straps compatible with the Breitling Chronomat 40 GMT A32398A21L1A1?

Yes, the Breitling Chronomat 40 GMT A32398A21L1A1 features a standard 20mm lug width, compatible with a wide range of artisan aftermarket straps. It is essential to verify that the chosen strap has straight (not curved) ends to ensure a correct fit against the lug geometry of this specific model. Milano Straps offers a curated selection of compatible 20mm straps available online.

How long does a leather strap last on a Breitling Chronomat 40 GMT?

The lifespan of a leather strap depends on the material, care and frequency of use. A quality shell cordovan or alligator strap with hand-finished edges and vegetable tanning can last between three and five years with regular wear, developing a personal patina over time. Prolonged exposure to water and perspiration should be avoided, and a leather conditioner applied periodically to maintain the grain structure.