Introduced at Baselworld 2013 by the revitalized Arnold & Son brand, the UTTE (initials are for “Ultra Thin Tourbillon Escapement”) quickly garnered attention when it became — without necessarily meaning to, according to Arnold & Son head of movement development Sebastian Chaulmontet — the thinnest tourbillon watch on the market. The watch’s case, available in either rose gold ($69,050) or palladium ($59,950), is just 8.34 mm thick and 42 mm in diameter. The flying-tourbillon movement, Arnold & Son’s A&S8200, is just 2.97 mm thick (not counting the height of the tourbillon cage, which rises above the dial) and packs 90 hours of power reserve into two barrels.