The subtle 18K rose Gold mechanism with its two perfectly synchronized beating mechanical hearts for an unequaled precision in a wristwatch are visible through a sapphire crystal case-back. The 2019 edition of the Chronomètre à Résonance is available in two versions: one with a Platinum case and white Gold dial, the other entirely in 18K 6N Gold. The two dials in Silver guilloche Clous de Paris indicating the hours and minutes can also be set on two different time zones.