335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets, subclass 66 for electromagnetically operated switches with electrothermal time delay means.
(Electricity: Magnetically Operated Switches, Magnets, and Electromagnets; subclass; 66; for electromagnetically operated switches with electrothermal time delay means)
Electricity: Magnetically Operated Switches, Magnets, and Electromagnets
subclass
66 for electromagnetically operated switches with electrothermal time delay means