The product is a set of two vintage IBM Electrographic Mark Sensing Pencil Leads, one partially filled and one full. These leads are made of graphite and were manufactured in the United States. As collectible items, they hold historical significance as relics from the era of electrographic pencils, offering a unique glimpse into the past of writing instruments. The IBM brand adds to the appeal for collectors interested in vintage pens and pencils.
For use in optical character recognition, if you are "of a certain age" you took tests and examinations using IBM pencils and leads like these.