This is a vintage Keuffel & Esser slide rule with case. The last known use of this slide rule was by a University of Chicago student during the 1940s, and it has been in retirement ever since. 

K & E Log Log Trig Trade Mark appears on the top of the case.  It has the number 4090-3 on one edge of the moving strip and the number 506400 at the other. It has one cursor (or runner) that moves freely. The case bears the name Ben Oniki University of Utah beautifully etched in several places on the outside and one on the inside. The case shows some wear and smudges from use and age, but it closes neatly with a strip through a holder

Proceeds benefit Beaver Area Memorial Library, Beaver, PA.  This item will ship anywhere in the U.S. via USPS ground advantage.  No international bids, please.  Thanks for looking and bidding.