For URWERK, a precision timepiece should have at its base a movement that is accurate, reliable and long lasting. Such a movement should meet specific criteria including accuracy in 5 positions between -4 seconds and +6 seconds over 24 hours. However, while it is one thing to regulate an accurate watch in the controlled world of a workshop, performance in the sometimes-extreme real world, i.e. on the wrist, can be very different. Changes in position and temperature, and shocks, can all adversely affect isochronism (timing regularity) of a wristwatch. The challenge with EMC was in developing a mechanical watch that can be regulated by its owner to obtain the finest chronometric performance. EMC is the first precision mechanical watch that enables timing to be both easily monitored and easily adjusted by its owner…..