The GE No. 5 is a classic medium-large single-use flashbulb widely used in professional and serious amateur photography throughout the 1950s and 1960s, compatible with the larger reflector-style flash guns of the era. Made in the USA and sold under GE's Guaranteed Flashbulbs line, the No. 5 was suitable for black and white, Kodacolor, and Ektachrome F color slide film. The clear uncoated glass indicates these were intended for black and white or tungsten-balanced film use. A full unused box in original packaging is increasingly hard to find and makes this a notably complete and desirable example.