Arnold & Son continues its tour of the Ultrathin Tourbillon collection. The A&S8320 calibre unveils its curves, apertures and details within a 41.5 mm case in either 18K 5N red gold or .950 platinum, each released in a limited edition of 28 timepieces. Encased in this precious housing, Arnold & Son’s flying tourbillon stands out for its finesse and precision.

With its graceful curves and wide apertures, the new Arnold & Son Ultrathin Tourbillon Skeleton also stands out for its slimness. Its new case, with a diameter of 41.5 mm and a thickness of 8.4 mm, presents the flying tourbillon calibre in its purest expression. The Ultrathin Tourbillon Skeleton collection, adorned in red gold or platinum, is issued in two limited series featuring 28 watches apiece.

Finesse, because at just 3.3 mm thick, it is one of the slimmest skeleton tourbillon calibres in existence. Precision, because this one-minute flying tourbillon is assembled with a variable-inertia balance for enhanced calibration stability.

The purpose of a skeleton is to convey a message, be it geometric, generic, or minimal. For Ultrathin Tourbillon Skeleton, the skeletonization of the calibre reveals pronounced curves and numerous inflection points that are highlighted by an original finish. On both the Ultrathin Tourbillon Skeleton Red Gold and Platinum, the bridges are treated with rose-gold PVD 4N after being decorated with radiating Côtes de Genève stripes.

The flange around the calibre adopts this same finish, clearly revealing the Arnold & Son signature at 6 o’clock and enabling the off-centered white opal dial to be displayed in its purest form. At the heart of Ultrathin Tourbillon Skeleton beats the A&S8320 calibre, whose architecture and slimness are its principal protagonists. Designed without an upper bridge to minimize its thickness, the calibre is classed as a flying tourbillon. The variable-inertia balance with inertia blocks ensures more precise calibration over time. The slender triangular carriage is supported by a double arrow, which is a counterpoise. The arrowhead on the staff of the escape wheel serves as a seconds pointer, as the carriage completes one rotation per minute.

The changes to the tourbillon carriage and regulating organ give the A&S8320 calibre a power reserve of 100 hours. While this is a larger power reserve than for standard tourbillons, particularly slim ones, it is entirely in line with the performance regularly achieved by Arnold & Son calibres.

While the 5N red gold model is delivered on a hand-stitched blue alligator leather strap with a black alligator leather lining; the platinum model is delivered on a hand-stitched brown alligator leather strap also with a black alligator leather lining. Both models are equipped with a folding clasp in titanium with a buckle in 18K 5N red gold or platinum respectively and are available in a highly exclusive limited edition of only 28 pieces each.

Sticker Price USD 74,400 for red gold and USD 86,200 for platinum. For more info on Arnold & Son click here.