The Citizen 4-S39717 watch movement, developed by Jaeger-LeCoultre, showcases the renowned 'Gyrotourbillon' complication. This caliber comprises 373 components and boasts a power reserve of 50 hours. The tourbillon mechanism comprises an outer carriage made of aluminium, completing a full rotation every 60 seconds, and an inner carriage crafted from titanium and aluminium, rotating completely every 18.75 seconds. The balance wheel possesses an inertia of 12.5 mg x cm2 and operates at a frequency of 28,800 vibrations per hour. The movement consists of 100 individual parts. Additionally, the Citizen 4-S39717 movement offers variations with both sweep seconds and non-sweep seconds, and it features an automatic winding system.