Breitling · Exospace

Strap for B55 Exospace Titanium / Black / TwinPro Blue / Folding

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

Lug width

24mm

24 mm straps All Breitling

Lug width24 mm

Case diameter46 mm

ReferenceEB5510H21B1S1 (aka: EB5510H2/BE79/235S/E20DSA.4)

FamilyExospace

MovementBreitling caliber B55 Additional 24 hours Hand (adjustable), hours, minutes, seconds | date, day, month, perpetual calendar, year indicator | Chronograph, countdown, Flyback, Rattrapante | alarm | chronometer, power reserve indicator, connected

Year2016

CaseTitanium

Spring bar

Swiss Standard universal spring bars

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

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Straps for the Exospace EB5510H21B1S1 (aka: EB5510H2/BE79/235S/E20DSA.4)

Selected for the 24 mm lug width · workshop selection

All 24 mm straps →

The Exospace EB5510H21B1S1 (aka: EB5510H2/BE79/235S/E20DSA.4), seen from the bench

The Breitling Exospace B55 (reference EB5510H21B1S1) is a wrist-mounted avionics instrument designed for professional pilots. The 46mm titanium case houses the Caliber B55, a thermally compensated SuperQuartz electronic movement with COSC chronometer certification. Features include flyback chronograph with rattrapante, perpetual calendar, countdown, alarm, and adjustable 24-hour hand. The 24mm lug width is specific to Exospace architecture and must be verified precisely before fitting an aftermarket strap.

Frequently asked questions

What is the lug width of the Breitling Exospace EB5510H21B1S1?

The Breitling Exospace EB5510H21B1S1 has a lug width of 24mm. This dimension is intrinsic to the 46mm case architecture and is essential for selecting an aftermarket strap that fits precisely without lateral play.

What is the best strap for the Breitling Exospace EB5510H21B1S1?

It depends on the context. For formal settings, a vegetable-tanned alligator strap complements the brushed titanium case with refined contrast. For operational or daily use, vulcanised rubber or ballistic nylon NATO straps align naturally with the watch's avionic vocation.

How do I change the strap on the Breitling Exospace EB5510H21B1S1?

The strap is replaced via the springbars seated in the case lugs. Use a fine-tipped springbar tool to avoid scratching the brushed titanium. The operation takes approximately two minutes and requires no specialist watchmaking skills.

Are there aftermarket straps compatible with the Breitling Exospace EB5510H21B1S1?

Yes. Any strap with an exact attachment width of 24mm is technically compatible. Milano Straps offers a curated selection of handcrafted leather, alligator, NATO and rubber straps in the 24mm size, each tested for precise fitment on this reference.

How long does a leather strap last on a Breitling Exospace EB5510H21B1S1?

Longevity depends on the leather type and frequency of wear. A quality vegetable-tanned calf strap, with regular care, typically lasts 12 to 24 months. High-grade alligator straps, owing to the density of the grain and the robustness of the hide, can exceed 3 to 4 years while developing a distinctive patina.

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