Breitling · Navitimer

Strap for Navitimer Rattrapante Stainless Steel / Black / Calf / Pin

Takes 24 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width24 mm
Case diameter45 mm
ReferenceAB031021/BF77/443X/A20BA.1
FamilyNavitimer
MovementBreitling caliber B03 hours, minutes, small seconds | date | Chronograph, column wheel, Rattrapante | chronometer
Year2018
CaseStainless Steel

Spring bar

Swiss Standard universal spring bars

The right category for this model · 316L steel, all lug widths 13–26 mm

Straps for the Navitimer AB031021/BF77/443X/A20BA.1

Selected for the 24 mm lug width · workshop selection

All 24 mm straps →

The Navitimer AB031021/BF77/443X/A20BA.1, seen from the bench

The Navitimer is one of Breitling's most iconic chronographs, featuring the circular slide rule for aviation calculations. It is powered by the automatic B03 caliber with split-second chronograph function and chronometer certification. The 24mm lug case and column-wheel operated chronograph complete the technical configuration of this model.

Frequently asked questions

What is the correct lug width for the Breitling Navitimer AB031021/BF77/443X/A20BA.1?

The lug width of this model is 24 millimetres. This specific measurement is unique to the modern Navitimer and ensures visual proportion with the 45mm case diameter. To verify compatibility, measure the distance between the two metal pins (lugs) that attach the strap to the case—it must be exactly 24mm. Do not confuse this with the lug thickness, which is determined by the case geometry.

What strap material is most suitable for a Navitimer chronograph?

Alligator leather with vegetable tanning represents the most rigorous choice: it offers tactile refinement, natural patina over time, and mechanical durability. For everyday versatility, textured calf with stainless steel deployant buckle allows rapid adjustments. A NATO strap in technical canvas references original aviation heritage, whilst antistatictechnical rubber with subtle texture maintains contemporary sportiness in modern transitional environments.

How do you change the strap on a Breitling Navitimer AB031021?

The procedure requires a spring bar tool (pin removal lever). Insert the tool tip into the lateral recess of the upper pin and lift gently to release the spring-pin from its seat, then repeat at the base. The old strap will now release from the case. For installation, align the new strap's inner hole with the pin and reinsert the spring bar, compressing the spring with the lever until the pin clicks into the seat. Verify engagement by gently pulling the strap.

Are aftermarket straps available that are compatible with the Navitimer AB031021?

Yes, numerous artisans and specialist brands manufacture aftermarket 24mm straps. Milano Straps offers dedicated 24mm strap collections, customisable in leather, colour, initials, and stitch type. Compatible straps must feature two lugs (or lug holes) spaced exactly 24mm apart. Before purchase, verify the strap is certified for this specific measurement to avoid mounting errors.

What is the typical lifespan of a natural leather strap on this Navitimer?

A quality artisanal alligator or calf strap, utilised daily with regular rotations, has an average lifespan of 3–5 years. Longevity depends on: frequency of use, exposure to moisture and sunlight, periodic maintenance (cleaning, conditioning), and tanning method. Vegetable-tanned leather tends to absorb and oxidise naturally, developing desirable patina but shortening mechanical life. NATO canvas straps exceed 5–7 years if subjected to minimal tensile stress.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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Casati Milano · Via XX Settembre 15, Milan · by appointment only