A plastic pocket slide rule in case
This pocket slide rule represents one of the last models made in China, before slide rules were superseded by electronic calculators. It is a basic rule used for trigonometric calculations, made in plastic by the National Light Industrial Products Import and Export Corporation under its brand name, Flying Fish.
Slide rule production in China appears to have started after World War II and the Shanghai factory is known to still exist. The Chinese rules sometimes appear to have borrowed style and scale features from western makers. The finish and assembly of the scales could vary from rule to rule; for example, multi-line cursors were common, and the scales were engraved and filled in black or red pigments which were not especially water fast, so care must be used in cleaning.