Very Rare Post Model 1491 Slide Rule For Chemical Engineers--Sun Hemmi 257

Good used condition. Leather case has Some dings and scuffs from age, which is to be expected. I was going to condition the leather, but sometimes buyers like the “aged, used” look. The unit itself is in great condition for its age, slides like it should. Viewing piece is not broken. Please ask if you have any questions. Thanks!