Concise Circular slide rule 28 English Version, made in Japan 1968 Instrument Adjust the stones closer or

Adjust the stones closer or further apart by turning the locking handscrew opposite the handle

it works work great because it has no moving parts like fans

defying what most would think of from this "portrait" lens

This is in superb working condition

1X Hdmi Output

Concise Circular slide rule 28 English Version, made in Japan 1968 Instrument Adjust the stones closer orMy Dad gave me this when I was in H. S. in 1968, I never used it (and neither, I doubt, will you) I've owned this for 58 years, so I'm listing it as USED however its in as new condition with its original manual and packaging sleeve. English specifications for Slide Rule No. 27 This is the most popular circular slide rule, and it is a basic slide rule that can easily perform calculations other than addition and subtraction, such as multiplication,