The beat accuracy of watches is influenced by magnetism. The mechanical movement should be demagnetised either in the assembled or dismantled state after every service and cleaning.

Particularly the balance spring, mainly for older movements, can have become magnetised over time. Any harmonic oscillation of the spring is then no longer possible: The watch does not run accurately. Tool can also represent a "source of danger" and transfer magnetism and should therefore be demagnetised before use with watch movements.

Elma Antimag demagnetises complete watches (attention: electronic quartz watches must not be demagnetised), dismantled movement parts, case and tools in milliseconds by pressing a button.