The Unbrako Vintage Slide Rule is a nostalgic tool with plastic scales featuring letters A, B, CI, C, D, and K. This calculator from a bygone era is a testament to the craftsmanship of old-school design and functionality. The simplicity and elegance of the slide rule make it a sought-after collectible for vintage tech enthusiasts and students of mathematical history. Unbrako promotional slide rule. Closed frame, plastic, with scales:A{B,C1,C}D,K/ It appears to be a Kutsuwa No. 93 I am selling this very rare slide rule as shown in pictures, real pictures, in excellent condition.
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