Concise ruler 28N 100973 English Ver. Circular slide rule

Concise Ruler Circular Slide Rule No. 270N 100812 F/S w/Tracking# New from Japan

Ruler Circular Slide Rule No. 270 Made IN JAPAN

Concise ruler circular slide rule 28N 100973 English Ver.

Scientific Instruments Co. Circular Slide Rule 1962 No. 1290 with Case

Concise ruler 28N English Version Circular slide rule made in Japan *US seller

Concise Circular Slide Rule NO. 28N 100973 (English Version) Ruler w/ Tracking #

Concise Ruler Circular Slide Rule 28N 100973 Dedicated Storage Case Included