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Omega

Omega cal 3861

Co-Axial (Omega) · introduced 2021
Beat rate
21,600 vph
Power reserve
50h
Jewels
33
Introduced
2021
Escapement
Co-Axial (Omega)

The cal 3861 replaced the 1861 in the current Speedmaster Moonwatch Professional, adding the Co-Axial escapement, a silicon balance spring, and METAS Master Chronometer certification to the iconic manual-wind chronograph platform. It is anti-magnetic to 15,000 gauss and rated to plus or minus 0/plus 5 seconds per day in the cased watch. A central bridge layout was retained to keep the familiar caseback view.

Specifications

Beats per hour
21,600
Jewels
33
Power reserve
50h
Diameter
28.0mm
Height
6.9mm
Escapement
Co-Axial (Omega)
Introduced
2021
Finishing
Fine
Service interval
8 years
Service cost tier
Luxury

Complications

chronographmanual wind

Known service issues

  • METAS status requires authorized service to restore after movement work

Notable in

  • Omega Speedmaster Moonwatch Professional 310.30.42.50.01.001
  • Omega Speedmaster Alaska Project 311.32.42.30.04.001

References in our catalog using this caliber

Buying advice

Practical guides for buying a watch with this caliber on the pre-owned market:

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Omega cal 3861 | movement specs | Grail Atlas