One of the biggest innovations in the Ultimate Concept is in the construction and assembly of the balance and balance spring. There’s no balance cock, and there’s no shock absorbing system, nor are there any jewels for the balance staff – that’s because there’s no balance staff either. Instead, the balance runs in a ball-bearing race set into the back of the watch case, which as we’ve mentioned functions as the base plate of the movement. The balance spring is placed below the balance (which is an inversion of the usual construction) and there’s no conventional regulating index either; instead, adjustment is done via a mobile stud. The omission of the balance cock, shock system and jewels is probably one of the biggest factors responsible for the dramatic reduction in height over the 900P.