Chapter 4 Onyx Flying Tourbillon

The Architect

ExpertOct 11, 2026

75

BA111OD occupies a peculiar coordinate within the contemporary independent watchmaking topology — a brand whose commercial identity orbits accessible irreverence, here producing an iteration that reaches, perhaps unexpectedly, toward genuine horological ambition. The Chapter 4 Onyx Flying Tourbillon presents an onyx dial of considerable formal authority: the stone's natural stratification interacts with the exposed tourbillon aperture in a manner that rewards extended observation, and the handset maintains sufficient visual discipline against the dark ground to avoid the legibility failures that plague similarly conceived dress references. Concordantly, the caliber BA.02 represents a meaningful engineering commitment for a brand of this scale — 120 hours of power reserve in a manually wound flying tourbillon configuration, housed within 9.75 millimeters of case thickness, reflects considered movement architecture rather than specification inflation. The case itself, at 41 millimeters in stainless steel, is proportionally uncontroversial, though it offers no particular formal distinction from its contemporaries. The calf leather strap is adequate without elevation — a component that does not diminish the piece but contributes nothing to its thesis. The value proposition warrants scrutiny: $12,249 positions this reference against established maisons offering comparable tourbillon complications with demonstrably deeper horological lineage. As you undoubtedly gather, the probability that provenance-conscious buyers prioritize BA111OD over those predecessors is not negligible, but neither is it certain.