Omega Caliber 8520

Brand	Omega
Caliber Number	8520
In-House	Yes
Movement Type	Automatic
Jewels	28
Power Reserve	50 hours
Vibrations Per Hour	25,200bph
Hairspring	Silicon Si14
Shock System	Nivachoc
Escapement	Co-Axial
Features	Hours, minutes, date at 3:00
Country of Manufacture	Switzerland
Known Models	37.5mm Planet Ocean, Ladies Constellation, 34mm Aqua Terra (add yours in the comments below…)

The Omega caliber 8520 is an in-house automatic movement found in smaller ladies and mid-size Omega watches.

In Omega’s own words:

Self-winding movement with Co-Axial Escapement for greater precision, stability and durability. Free sprung-balance system with silicon balance-spring. Automatic winding in both directions to reduce winding time. Rhodium plated finish with exclusive Geneva waves in arabesque.

Watches with this movement:

At the time of this post, Omega has 164 models with the caliber 8520. The image above is an 8250 example from a ladies 31mm Constellation watch. Some other models include:

• Aqua Terra (30mm)
• Aqua Terra (34mm)
• Constellation (27mm)
• DeVille Ladymatic (34mm)
• Planet Ocean (37.5mm)

Video Manual:

Additional Resources:

• Read more: Testing Omega’s Seamaster Aqua Terra
• Video: George Daniels, The Master Rests