Technical Archive

Breitling
Chronomat Evolution A1335611/B721— lug 20mm

Breitling Chronomat Evolution A1335611/B721: 20mm strap. Alligator, box calf, shell cordovan and rubber, cut and stitched in Milano. Choose your leather.

Chronomat Evolution Stainless Steel / Black

Artisanal Note

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

Technical Specifications

Breitling A1335611/B721
Lug Width
20 mm

The essential strap measurement.

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Reference

A1335611/B721

Movement

Breitling caliber Caliber 13 Hours, Minutes, Small Seconds | Date | Chronograph

The Heritage

The Chronomat Evolution represents the evolution of Breitling's 2000s sports line. It is equipped with the automatic caliber 13 with hours, minutes, small seconds, date and chronograph functions. The reference A1335611/B721 maintains the distinctive features of the collection with a unidirectional bezel and chronograph pushers.

FAQ

What is the lug width of the Breitling Chronomat Evolution A1335611/B721?

The lug width of the Breitling Chronomat Evolution A1335611/B721 is 20mm. This measurement is taken at the inner distance between the lugs at the spring bar attachment point. Any standard 20mm strap will be compatible with this reference.

What is the best strap for the Breitling Chronomat Evolution A1335611/B721?

The ideal choice depends on intended use and aesthetic preference. For a refined look, a belly-cut alligator strap paired with a brushed steel deployant clasp complements the instrument-grade character of this chronograph. For sport or summer use, a vulcanised rubber strap offers superior grip and moisture resistance. Shell cordovan is recommended for those seeking long-term durability and a noble patina that develops with wear.

How do you change the strap on a Breitling Chronomat Evolution A1335611/B721?

Strap replacement requires removing the spring bars that connect the strap to the case lugs. A forked spring bar tool or a dedicated watch lever is used for this purpose. Care should be taken to protect the steel lugs from scratching — a soft pad beneath the watch is advisable. Alternatively, any watchmaker can perform the swap in a matter of minutes.

Are there aftermarket straps compatible with the Breitling Chronomat Evolution A1335611/B721?

Yes. The 20mm lug width is one of the most widespread standards in watchmaking, ensuring broad compatibility with quality aftermarket straps. Milanostraps.it offers a curated selection of artisanal leather, rubber and textile straps in 20/18mm width, with lengths suited to the 43.7mm case of the Chronomat Evolution.

How long does a leather strap last on a Breitling Chronomat Evolution A1335611/B721?

With standard care — drying after moisture exposure, rotating between multiple straps and occasional conditioning — a quality artisanal leather strap typically lasts between two and four years. Alligator and shell cordovan, owing to their fibre density, offer greater longevity than standard calf leather. Casati Milano provides an 18-month production defect warranty on all atelier straps.