HMC 901

The hand-wound HMC 901 calibre measures 28.8 x 33.55 mm with a height of 6.25 mm, operating at 21,600 vph with 28 jewels and a minimum 87-hour power reserve. It features a flat hairspring, hand-finished components with double Moser stripes, a one-minute flying tourbillon at 6 o'clock with a skeletonised bridge, and a minute repeater. Developed with MHC Manufactures Hautes Complications SA, this shaped movement integrates a minute repeater and tourbillon, featuring two rectangular gongs that are challenging to tune. Additional: Tourbillon Escapement.