Keuffel & Esser 4081-3

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Who doesn't have a few of these knocking around? This is the K&E 4081-3, the workhorse of the K&E line, and one of the most popular slide rules ever made. This celluloid-over-mahogany rule was also known as the N4081 and the 68-1210 at various times during its production.

Front: LL02, LL03, DF, CF, CIF, CI, C, D, LL3, LL2
Back: LL01, K, A, B, T, ST, S, D, L, LL1