L.U.C Calibre 97.03-L is a tonneau or barrel-shaped calibre. Shaped movements represent a difficult exercise in that designing them involves entirely revising the arrangement of the parts in order to match an unusual mainplate. But since one of the fundamental principles of Haute Horlogerie is to adapt the shape of the movement to the shape of the case, only the most prestigious manufactures have shaped movements in their range of technical resources, and Chopard Manufacture is no exception to this rule. L.U.C Calibre 97.03-L is an ultra-thin tonneau-shaped calibre measuring just 3.30 mm thick. Its bidirectional self-winding movement is equipped with a 22-carat gold micro-rotor, enabling it to be incorporated into the thickness of a movement that thereby remains as slim as ever. Thanks to its L.U.C Twin technology, it has a 65-hour power reserve, and its precision is accredited by a chronometer rating certificate issued by the Swiss Official Chronometer Testing Institute (COSC).