The Old Keuffel & Esser (K&E) USA Polyphase Duplex #4168 Slide Rule is a vintage engineering tool manufactured in the United States. This 6" slide rule is a specialty tool used for calculations in engineering and scientific fields, particularly in the measurement and conversion of units. The K&E brand is known for producing high-quality scientific instruments, making this slide rule a valuable collectible for enthusiasts and professionals alike.
Please review all the photos and make sure this slide rule is up to your quality standard.It is in remarkably good condition.The box does show shelf wear, if you have any questions, Please ask and thank you for reading the description.