Adam-12 was set in LA Who or what Adam-12?

"Adam-12" is not a person or thing, but the name of a popular American police drama television series that aired from 1968 to 1975. The series followed the daily lives of two Los Angeles Police Department (LAPD) patrol officers, Pete Malloy (played by Martin Milner) and Jim Reed (played by Kent McCord), as they responded to calls and dealt with a variety of situations in their patrol car, a 1968 Ford Galaxie 500.

So, the name "Adam-12" refers to the television series itself, which was set in Los Angeles, California.