How it works: When the lever is pressed, the two copper strips are pushed forward and come into contact with an electromagnet that begins the simple toaster circuit.

The current flows through a large resistor that wraps around the toaster and slowly gets hot which is what allows the bread to cook.

A capacitor connected to the circuit charges through the resistor, and when it reaches a certain voltage it stops the flowing current.

The spring immediately pulls the slices of bread up.

In the process, the lever rises and cuts off power to the toaster.

The darkness setting (below the lever) uses a bi-metallic strip which heats up when the circuit is on and depending on what setting you have it on, the strip bends for a certain amount of time and eventually trips a switch that kills the power to the electromagnet.