In SMOT, a steel ball is pulled up a ramp by magnetism and then falls, so the magnetic energy is converted into kinetic energy. Watson claims that an effect called "regauging" then happens, allows the process to be repeated without the application of outside energy.
Adherents say the device must be carefully tuned to work, and attribute any failures to poor adjustment. Skeptics note that many attempts have been made to use magnetism to overcome entropy, without success.
The SMOT structure is also shown in the patent US4215330 of Emil T. Hartman. There are some predecessors and structures differ slightly, though they have common features.