Zenith's Defy is now a collection in its own right, with models that range in complexity from hours-minutes-seconds to grand complications. The Defy Zero G belongs to the latter category. Its focal point is the Gravity Control module that Zenith has integrated into a grey-toned and skeletonised high-frequency El Primero movement. This patented gyroscopic module, which made its debut a few years ago on different Christophe Colomb watches, has been optimised for the Defy Zero G while continuing to cancel the effects of gravity on the watch's rate by maintaining the regulating organ and balance wheel in a horizontal position – exactly like a Marine Chronometer in gimbals. This spherical system comprising 139 components has also been downsized and now occupies just 30% of its initial volume to fit perfectly between the two flat sapphire crystals of the Defy case.