Start with what the Opel 10/12 PS is: a car with gasoline engine, from Opel. What it meant takes a little longer.
What is underneath
The engine is gasoline engine. On the scales it comes to 700 kg. These are manufacturer figures carried by Wikipedia and Wikidata, not road-test measurements.
Its place in the line
Nearby in the Opel catalogue sit the Opel Sintra and the Opel K-180.
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