/A20BA.1 Cosmonaute Limited Edition

In Context

At 43 mm it is a large watch — well above this catalogue’s 40 mm median, and enough to dominate a narrow wrist. At 13.9 mm it is a tall case, and it will catch on a cuff. The case back is closed, so the movement stays out of sight, and the sapphire crystal will resist everything short of deliberate abuse.

The movement is hand-wound, so winding it becomes part of the day rather than something the watch does for you. 70 hours of reserve is enough to set it down on Friday evening and find it still running on Monday. At 28,800 vph the seconds hand advances 8 times a second.

AB021012/BB59/435X stands on its own in this catalogue — no other reference here shares its base number. It pairs a black dial with a stainless steel case. It was a limited edition.

The B02 is the hand-wound version of Breitling's B01 chronograph with a 24-hour dial, made for the Navitimer Cosmonaute. It powers 15 watches in this library, every one a Cosmonaute. The 1962 Cosmonaute had a 24-hour dial so that Scott Carpenter could tell day from night in orbit, and it became the first Swiss wristwatch in space on his Aurora 7 flight; the modern Cosmonaute keeps the dial and the slide rule. The B02 is the in-house [B01](/calibers/breitling-caliber-b01), a column-wheel chronograph with a vertical clutch and a 70-hour reserve at 28,800 vph with 47 jewels, with the rotor removed and the hour hand geared to turn once a day. It is COSC-certified. In the library it powers 15 [Navitimer](/brands/breitling/navitimer) Cosmonaute references: 9 at 43 mm from the 2010s and 6 of the Navitimer B02 Chronograph 41 Cosmonaute of 2022. 7 are limited editions. The [B01](/calibers/breitling-caliber-b01) is the automatic base, and the [B09](/calibers/breitling-caliber-b09) the hand-wound B01 with a conventional dial in the Premier Heritage and the AVI Ref. 765.

14 other watches in the library run the Breitling Caliber B02.

Breitling

Navitimer B02 Chronograph 41 Cosmonaute Stainless Steel - Platinum / Japan

PB02302A1B1A · 41 mm

Breitling

Cosmonaute Blacksteel / Black / Rubber / Folding

MB0210B6/BC79/200S/M20DSA.2 · 43 mm

Breitling

Cosmonaute Stainless Steel / Blue / Bracelet

AB0210B4/C917/447A · 43 mm

Breitling

Cosmonaute Stainless Steel / Black / Croco

AB0210B4.BC36.743P · 43 mm