This is for the younger crowd that has never adventured into an electric furnace.
First pic shows one side of the electrical terminal that connects to the heating element where I take the amp readings at.
Second pic shows the electrical sequencer that is activated by the thermostat to bring on the heat mode. This sequencer is older than dirt as a matter of fact have not observed any other sequencers that had this physical shape.
Third Pic shows the heating element. Nichrome wire strung on ceramic insulators.