Master Chronometer?

Theognosis

The way I understand:

A. "Co-axial" - Watch features Co-axial escapement

B. "Master" - Omega's terminology for their amagnetic watches, but not necessarily METAS certified.

C. "Chronometer" - COSC certified movement (no watch case), no results online

D. "Master Chronometer" - METAS certified watch (with movement inside) with test results available online. Note: movement is COSC certified prior to METAS testing. METAS testing includes clock precision, resistance to 15,000 Gauss magnetism and water resistance in accordance to depth rating.


Hence,

Co-axial / Master Chronometer = A + D

Master Co-axial / Chronometer = A + B + C

Speedmaster Professional = None of the above 😀