Albert Nestler 

Albert Nestler AG, a German company based in Lahr, Germany, founded by Albert Nestler. The slide rule factory stopped production in 1978, exactly 100 years after its conception. Before World War II, Nestler sent its slide rules to 60 countries !  Albert Nestler KG was one of Germany's leading slide rule manufacturers, together with Aristo and Faber-Castell. They originally had wooden body slide rules with celluloid scales, and then converted to plastic body slide rules after World War II along with other manufacturers.
The first wooden body slide rules closely resemble the Faber-Castell models and can easily be mistaken for them. The manufacturer's name and model number were usually found inside the body cavity under the slide, for many of the earliest wooden slide rules, so it wasn't always obvious who made a particular slide rule.