Smaller pocket slide rule by Aristo from Germany. This is the model 814 Electro and comes with:
- slide rule in great condition
- it’s original Aristo signed leather pouch in great condition
- a manual in English  in rougher condition with some partial paper missing
- original cardboard outer box in rougher condition, missing some pieces
The snug fitting box measures ca. 21 cm or 8 1/4 inches long, the rules measures 15,5 cm or 6 1/8 inches. See the attached video on how to work your vintage man tool : slide rule operation instructions!