Start with what the Buick Model 41 is: a car with gasoline engine, from Buick. What it meant takes a little longer.
The engineering
The engine is gasoline engine. On the scales it comes to 1540 kg. These are manufacturer figures carried by Wikipedia and Wikidata, not road-test measurements.
Where it sits
Its Buick stablemates include the Buick First Call and the Buick Funeral Car.