with built-in device, e.g. switch, for automatically completing circuit of reserve body

Full Title

Lamps having two or more incandescent bodies separately heated > to provide substitution in the event of failure of one of the bodies > with built-in device, e.g. switch, for automatically completing circuit of reserve body

Classification Context

Section:

ELECTRICITY

Class:

ELECTRIC ELEMENTS

Subclass:

ELECTRIC INCANDESCENT LAMPS