The age-old fusee and chain mechanism has held its place in history for the last six centuries as the equaliser which evened out the pull of the mainspring. Its purpose? To improve the precision of timekeeping. Zenith has long been a well-appreciated name when it comes to implementing the “constant force” of the fusee and chain system in their timepieces. We are, but of course, talking of the Zenith Academy Georges Favre-Jacot watch. Named after the founder of the Le Locle based brand, the timepiece was recreated in 2014 to commemorate 150 years of its inception and houses the intricate fusee and chain system.

Fast forward to 2019, and we welcome the new Defy Fusee Tourbillon, an avant-garde attempt by the brand commemorating the movement architecture of the “constant force” mechanism. Available in two distinct editions of Carbon and Platinum, the latest addition to the Defy collection houses the manual-winding El Primero 4805 SK calibre allowing an open three-dimensional impact to the watch.

The calibre features the conceived fusee and chain mechanism on top of it. The chain consists of 575 individually hand-assembled components in a very first bold blue hue. The 6 o'clock on the other end features a matching blue tourbillon cage with an off-centred balance wheel making a full rotation every 60 seconds. The 4 and 5 o'clock hour makers house the red-tipped power reserve indicator between them.

The first version of the Defy Fusee Tourbillon comes in a lightweight carbon case, crown and buckle head. The open dial features a carbon fibre treatment including the central skeletal element. Limited to 50 pieces, the Carbon watch sits comfortably on a black rubber strap with a “Cordura” fabric effect and blue stitching.

The second Platinum version, limited to 10 pieces, offers a vibrant view of the open dial in anthracite and blue. The strap is made of a black rubber core coated with black alligator leather.