Description
Class F21K : LIGHT SOURCES NOT OTHERWISE PROVIDED FOR
Subclass 5/10: Light sources using charges of combustible material, e.g. illuminating flash devices (explosive or thermic compositions C06B; fireworks F42B 4/00; photographic flash units G03B 15/03) Charge containment Charge held in non-disrupting container, e.g. photo-flash bulb bearing a coating