The Double Tourbillon Technique is an entirely original and innovative interpretation of Greubel Forsey’s first fundamental invention, the Double Tourbillon 30°. At the heart of the timepiece is the Double Tourbillon 30° mechanism?; however, to perpetuate the art of horology and contribute to its 21st century development, several additional technical elements have been added, including four fast-rotating co-axial barrels.