VTG K&E KEUFFEL & ESSER Co 20" Model N-4053-5 Slide Rule USA & Leather Case

VINTAGE K&E/KEUFFEL & ESSER N4053-5 20" WOODEN POLYPHASE SLIDE RULE & Case!

Antique 1900 K&E KEUFFEL & ESSER Co 20-1/2" Model N-4053-5 Wood Slide Rule USA

K&E Keuffel & Esser 7" Pocket Slide Rule 4181-1 with Dark Green Leather Case

K&E 68-1608 Polyphase Mannheim Keuffel & Esser USA Slide Rule &Leather Case rare

Vintage Keuffel & Esser Co. K&E Slide Rule 4088-3 With Leather Case Made in USA

VINTAGE Keuffel & Esser K&E Deci Log Slide Rule N4080-3 w/ Leather Case USA

Keuffel & Esser K & E 4080-3S Slide Rule W/ Case USA Vintage 1940s-1950s Nice