The "watts-volts" routine was not in the script. It was created by Bud Abbott and Lou Costello on the set.
This was the first Bud Abbott and Lou Costello film that did not contain musical numbers. As a result, it was their shortest film to date.
Contains two references to Bud Abbott and Lou Costello's classic baseball routine, "Who's on First." Lou's exclamation, "Next you'll be telling me Watt's on second base," tops off his watts/volts exchange with Bud. When they later turn on a radio and hear "Who's on First" they promptly turn it off in disgust.
Radio actor Walter Tetley, who plays the elevator operator who perpetually gets the best of Lou Costello in this film, would go on to become the voice of "Sherman" in the "Mr. Peabody" cartoons in Les aventures de Rocky & Bullwinkle (2000).
When Lou Costello shows up at the studio to claim his "Wheel of Fortune" prize, the music the studio orchestra plays is "You're a Lucky Fellow, Mr. Smith" from the previous Bud Abbott and Lou Costello film Deux nigauds soldats (1941).