1mm. Although AP promoted the watch as “Further-Thin,” admirers ongoing to make reference to it as “Jumbo” given its 39mm scenario. Other slight adjustments included a swap from a white day wheel to some black version on the blue and black dials along with the addition of a double-deployant clasp https://www.watchesworld.com/a-guide-to-10-of-the-best-dress-watches/