Telescopic Slide Rule. Otis King’s Patent No 183723. N6055.

Vintage Fuller's Spiral Slide Rule or Calculator by John Davis with Case c1944

Vintage Fuller's Spiral Slide Rule Calculator Stanley in box case - Circa 1920

British Thornton AD 050 1970s Vintage Log Slide Rule + Hard Case

Early Keuffel & Esser Slide Rule with Leather Case Made in USA

1960s Vintage British Thornton AD 050 Slide Rule In original plastic case.

PIC 3650 SLIDE RULE 1950’S RARE GOOD CONDITION - A G Thornton With Case.

RARE Keuffel & Esser Co. Log-Log Duplex Slide Rule No. 4092 (Not -3!) Early Rule