Premier Heritage B21 Chronograph Tourbillon Gaston Breitling

In Context

At 42 mm it is sized to the current mainstream: 40 mm is the median across every watch measured in this catalogue. The case back is open, so the movement is visible without taking the watch apart, and the sapphire crystal will resist everything short of deliberate abuse. 100 m is genuine swimming resistance — more than the shape of this watch suggests it would need.

The movement winds itself from the motion of your wrist. 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.

JB2120A61B1P1 stands on its own in this catalogue — no other reference here shares its base number. It pairs a grey sunburst dial with a white gold case. Introduced in 2022. Beyond the time it carries a chronograph and a tourbillon.

The B21 is Breitling's chronograph tourbillon: the in-house B01 chronograph with a tourbillon at 6 o'clock, introduced in 2021 for the Premier Heritage. It powers 15 watches in this library, every one 42 mm. The [B01](/calibers/breitling-caliber-b01) supplies the column wheel, the vertical clutch and the 70-hour reserve at 28,800 vph; the tourbillon replaces the balance's fixed position with a rotating cage, visible through an aperture in the dial, and the movement has 47 jewels. It is COSC-certified and finished for a display back, and it is Breitling's only tourbillon movement in production. The glossary defines the [tourbillon](/glossary/tourbillon). In the library it powers 11 [Premier](/brands/breitling/premier) B21 Chronograph Tourbillon references in red gold and platinum and 4 [Top Time](/brands/breitling/top-time) B21s, several in the Deus and Triumph editions. 7 are limited editions. The [B09](/calibers/breitling-caliber-b09) and [B15](/calibers/breitling-caliber-b15) are the hand-wound B01 derivatives of the same Premier Heritage series, and the [B25](/calibers/breitling-caliber-b25) the Datora with its full calendar.

14 other watches in the library run the Breitling Caliber B21.

P

Breitling

Premier Heritage B21 Chronograph Tourbillon Red Gold / Beige - Rainbow

RB21205A1G1P1 · 42 mm

Breitling

Premier Heritage B21 Chronograph Tourbillon Red Gold / Blue / Japan

RB21203A1Q1P1 · 42 mm

P

Breitling

Premier Heritage B21 Chronograph Tourbillon White Gold / Meteorite

JB21201A1G1P1 · 42 mm

Breitling

Premier Heritage B21 Chronograph Tourbillon Willy Breitling

LB2120171C1P1 · 42 mm