Quick Answer
The Omega Constellation Co-Axial 27 Brushed Yellow Gold / Diamond / MOP Stars 123.55.27.20.05.002 (aka: 12355272005002) features a mechanical automatic movement and does not require a battery. It remains powered through the natural motion of your wrist or manual winding via the crown.
Movement Details & Winding Guide for Omega Constellation Co-Axial 27 Brushed Yellow Gold / Diamond / MOP Stars 123.55.27.20.05.002 (aka: 12355272005002)
Because the Omega Constellation Co-Axial 27 Brushed Yellow Gold / Diamond / MOP Stars 123.55.27.20.05.002 (aka: 12355272005002) is a mechanical automatic watch, it relies on a mainspring and oscillating rotor rather than an electrical quartz battery. To ensure optimal amplitude and timekeeping accuracy in this Yellow Gold model, hand-wind the crown clockwise approximately 30 to 40 times from a dead stop before securing it back down.
Disclaimer: The video above is for example and general guidelines only. It may not be entirely specific to your exact model, and quality/accuracy depends on third-party availability. If in doubt, please refer to your specific watch handbook or consult a professional.
Required Power Source
This watch uses an automatic or hand-wound mechanical movement. It does not require a battery.
Watch Specifications
| Brand | Omega |
| Model Info | 27mm Yellow Gold • MOP dial |
| Movement / Power | automatic |
| Battery Code | N/A |
Frequently Asked Questions
Does the Omega Constellation Co-Axial 27 Brushed Yellow Gold / Diamond / MOP Stars 123.55.27.20.05.002 (aka: 12355272005002) require a battery?
No. This model is automatic/mechanical and generates power via wrist kinetic motion.
How do I wind the Omega Constellation Co-Axial 27 Brushed Yellow Gold / Diamond / MOP Stars 123.55.27.20.05.002 (aka: 12355272005002)?
Unscrew or pull the crown to position 1 and rotate clockwise 30–40 turns to build a full power reserve.