Slide Rule w Leather Case The Frederick Post Co

Slide Rule by Frederick Post Company Chicago 90, Illinois It appears to be missing the slide that goes over the ruler based on the pictures in the manual. Comes in a nice black leather case with directions. Features: • Vintage Post slide rule • Comes in black 13” leather case • Comes with direction manual • Made with Bamboo • Pat 2 000 337 • Made in Usa Condition: Pre-Owned Good It is missing the piece that slides over top. All items come from a smoke free, pet friendly home.