1. This rule was made in former Czechoslovakia.
2. The model name on the rule is "Studio Logarex". The documentation refers to it as "System Studio". The rule is, in fact, a close copy of the Aristo Studio 0968, made in (then) West Germany. The use of the phrase "System Studio" is interesting because it has analogies with "System Darmstadt" and "System Rietz" and it implies that they are making a rule to a generic scale arrangment rather, than is obviously the case, copying a rule.
3. The cursor also has the same lines as the Aristo Studio.
4. Comparing this rule with the Aristo Studio shows how close the copy is.