Ampoule

Ampoule (アンプール) is one of Larxene's joke weapons in Kingdom Hearts 358/2 Days. The other one is Demoiselle. As their name suggests, they are simply lightbulbs.

Design
An Ampoule "knife" is shaped like an incandescent light bulb. The grey handle is the screw cap of the light bulb. The "blade" seems to have a yellow tint along the edges, and the silver filament is faintly visible at the base of the blade. The rest of the blade is white.