A shunt for use in a socket of a string of lights resides in an otherwise typical lamp of a string of lights. The present shunt is a conductive spring held in position by a shunt housing between the two conductive terminals so that both of its curved lateral ends contact the terminals when the bulb holder is removed. When the bulb holder is inserted, a pushrod on the flat central portion of the conductive spring presses the spring down into a well in the shunt housing so that the curved lateral ends of the conductive spring are drawn away from the electrical terminals, thereby allowing current to flow through the Dumet wires to the filament.