This is the starting switch found inside a Leland motor. I know these were used on Both Simplex and Motiograph projectors. These typically had a 1/4 HP motor. I know these have to be extremely rare. If you have an old Simplex or Motiograph sound head that you want to get running with the original motor, than this is for you.

It probably was used in other applications but these are the ones I am aware of.

Thanks