This is a promotional postcard for Johnny Williams. The back of the postcard reads:
KHJ “Boss Jock” Johnny Williams
If you’ve ever dialed the Bossline when Johnny’s on you know he’s a guy who digs his listeners. Of course it’s often a problem to get through to John because radio listeners dig him. But you don’t need a telephone to pick up on the Williams sound ... it’s yours exclusively on KHJ!