How close to paper-thin can a timepiece be, without actually being cut out of paper? Bulgari seems to be on a mission to answer this question. Following the success of the Octo Finissimo Toubillon in 2014 (with a movement just 1.95mm thick), and the Octo Finissimo Minute Repeater in 2016 (with a movement 3.12 mm thick), the Italian brand is back with the world’s thinnest self-winding watch. Powered by the ultra-thin 2.23mm Calibre BVL 138, the whole watch is only 5.15mm thick. To say it easily slips under the cuff would be an understatement. Its presence on the wrist is barely noticeable – not because its looks leave much to be desired, but because on top of its waif-like proportions, it’s also feather-light, thanks to a thoroughly modern sandblasted titanium case.