Bruning 2401* 5in Slide Rule and Leather Case F*S Mid Century There are 6 covered access

There are 6 covered access ports 6x13”

I have owned this machine for ~30 years and used it regularly for optical coating and thin-film thermal evaporation

this book also offers an incisive narrative of the history of astronomy and an evocation of what we see when gazing at the stars

This is a complete manual and note that it will show some age and wear blemishes

Bruning 2401* 5in Slide Rule and Leather Case F*S Mid Century There are 6 covered accessBruning 2401 5in Slide Rule and Leather Case Really neat and very practical 1960s 5 inch plastic rule #2401 Simplex With Bruning Leather Slipcase. 5" scale, with 6" total length. Scales on both sides of the center post. Front Scale 12. 5cm A [ B, CI, C ] D, K \\ 5in Back Scale: [S, L, T ] Leather slipcase is unmarked, Made in the USA FREE standard shipping to the 48 contiguous United States