I have main unit.
type calculator
country USA
The Commodore SR-4190R — Scientific Calculator
The Commodore SR-4190R was a scientific calculator from Commodore’s mid-1970s range — products from the period when Commodore was aggressively competing in the calculator market through its ”computers for the masses” pricing philosophy. Commodore’s calculator business funded the company’s transition into personal computers, and the engineering relationships developed during this period — particularly with MOS Technology — directly enabled the Commodore PET and eventually the Commodore 64. The SR-4190R connects Commodore’s calculator heritage with its later computing legacy.