From a private estate comes this exceptional example of a classic American engineering instrument: the K&E Model 4081-3 Log Log Duplex Decitrig slide rule, preserved as a complete set with its original accessories.
Manufactured by Keuffel & Esser of New York, this model represents one of the firm’s most advanced full-size calculating tools from the pre-electronic era, when precision engineering depended on craftsmanship rather than circuitry.
Model 4081-3 slide rule
Original fitted leather case
Original K&E box
Instruction manual
Glass cursor with hairline indicator
Complete sets of this caliber are increasingly difficult to locate.
Well-preserved vintage condition consistent with careful ownership.
Smooth, precise slide movement
Scales bright, sharp, and fully legible
Cursor clear and intact
Leather case shows light, honest age wear
Box present with expected vintage handling marks
Manual included
Please examine photographs carefully as they form part of the description.
The 4081-3 “Log Log Duplex Decitrig” was designed for advanced engineering, scientific, and technical computation.
Key capabilities include:
Log-log scales for powers, roots, and exponentials
Duplex configuration with scales on both sides
Decitrig system using decimal degrees
Professional accuracy trusted by engineers and scientists
Before handheld calculators emerged in the 1970s, instruments like this were used to design aircraft, infrastructure, and early space-age technology.
Full-size professional rule (approx. 10–13 inches)
Hardwood core with precision celluloid facings
Metal end braces
Glass cursor with fine hairline
K&E slide rules remain among the most respected American instruments of their type. Complete examples with original packaging are particularly desirable for collectors, educators, and historically minded engineers.
An excellent addition to a scientific instrument collection or a distinguished display piece for office or library.
Carefully packed with protective materials to ensure safe arrival.
Shipped promptly from a smoke-free environment.