While Corum is known to use third party ebauches on their entry level watches, they do design and produce their own exclusive calibers, most famously the jewel that is the Golden Bridge developed with Vincent Calabrese.
What’s your favorite “most dramatic show-off” Tourbillon? I nominate the AP 2870 automatic where the whole dial highlights that function. I saw one at the manufacturer 20 years ago and still remember it. (Photos from web search) Cazalea ...
The watch above was also an idea developed from without AP. Here is the prototype that sold at Phillips a few years ago. It seems though that they were willing to take certain risks with ideas that were trailblazing. www.phillips.com (Beyner and G...
While Corum is known to use third party ebauches on their entry level watches, they do design and produce their own exclusive calibers, most famously the jewel that is the Golden Bridge developed with Vincent Calabrese.