From the Super Mario Wiki
It has been requested that this article should be rewritten and expanded to include more information.
The title of this article is conjectural; an official name for the article's subject has not been found, so it has been given a fitting title by editors. If an official name appears, it is requested that the article be moved to the correct name.
The Stereo Gun is a weapon used in Rap Land in the Super Mario Bros. Super Show episode "Bad Rap". It is shaped like a Boom-box and fires exploding records. It was used by King James and Princess Toadstool to liberate Rap Land.