Reference 215.23.40.20.04.001 pairs a 39.5mm stainless steel case with an 18kt rose gold crown and a blue ceramic unidirectional bezel — a combination that signals both purpose and refinement. The sapphire crystal carries an anti-reflective treatment, framing a blue dial fitted with luminous applied hour markers and a date window at 3 o'clock for clear underwater readability. A helium escape valve is built into the case for saturation diving use, and water resistance reaches 600 metres / 60 bar.
Inside runs the Omega Co-Axial Master Chronometer Caliber 8800, an automatic movement offering a 55-hour power reserve alongside METAS-certified precision and anti-magnetic performance. The hours, minutes, seconds, and date functions are all present, housed within a movement that represents a meaningful step in Omega's escapement development.
The watch is presented on a blue rubber strap secured by a stainless steel tang buckle, and the complete set includes the original Omega box and Master Chronometer papers. For those seeking a dive watch at the 39.5mm scale without a reduction in professional-grade specification, this Planet Ocean 600M makes a compelling case.
