This is a Vintage Autolite Voltage regulator New Old Stock Part # VRP 4001-C.
this part is new and has been boxed on the shelf for many years. The box, like most NOS parts is delicate, but the part is in excellent condition. A list of cars that is written on the yellow tag include: Chrysler - 1937-1939, DeSoto - 1938-1939, Dodge - 1937-1939, Nash - 1937-1938, Packard - 1937-1938, plus others that would need to be verified.