A great cover, which introduces the Joker’s versions of Batman’s signature car, plane and signal on Batman 37 (Oct/Nov 46).
The Joker equips himself with this gear as he rents his services out to other criminals, who can call for his help with the Joker-signal. Batman eventually uses it to lure the Joker out of hiding.
The basic premise of the story would be re-written and used as the basis for the original Killer Moth story in the 1950s. While the Joker-plane and Joker-signal would not endure, the Jokermobile would continue to appear, with various modifications, all the way into the 80s.