Strap for Chronomat B01 42 NFL New York Jets / Rouleaux

The lug width of the Breitling Chronomat B01 42 AB01342B1L5A1 is 22mm. This measurement is taken with a calliper at the point where the lugs meet the case. The standard taper towards the buckle is 20mm, ensuring balanced proportions on the wrist.

For the Chronomat B01 42, the most suitable materials are vegetable-tanned calfskin for everyday wear — which develops a natural patina over time — and belly-cut alligator for formal occasions. For sporting use or humid environments, a vulcanised rubber strap or a nylon NATO offer functional alternatives that remain visually coherent with the model's aviation heritage.

To replace the strap on the Chronomat B01 42, a spring bar tool is required. Insert the tool into the small hole on the side of the lug, compress the spring bar and slide the strap outwards. No specialised tools are needed, though it is advisable to work on a soft surface to prevent scratching the stainless steel case. Any watchmaker can perform the swap in a matter of minutes if preferred.

Yes, the Chronomat B01 42 uses a standard 22mm lug attachment compatible with a wide range of quality aftermarket straps. Milano Straps offers handcrafted straps in Italian leather, certified alligator and technical rubber, all supplied with replacement spring bars. It is important to ensure the strap end is compatible with the slight curvature of the Chronomat's lugs.

The lifespan of a leather strap depends on tanning quality, daily use and maintenance. A quality vegetable-tanned calfskin strap, with regular use and periodic conditioning, typically lasts 2–3 years. Shell cordovan, owing to its dense grain structure, can exceed 4–5 years while developing an admirable patina. Frequent exposure to water or perspiration significantly reduces longevity; in such conditions, alternating with a rubber or NATO strap is strongly recommended.