String-Horn

Bizarre combination brass and string instrument from "The Horn of Plenty of Trouble" story of Police Comics #87 (February 1949). Invented by amateur Cajun musician Casimir, it is desired by criminal Phonie Le Ghoum. The instrument is simultaneously blown and bowed with a violin bow. It turns out Le Ghoum wants it because when played, it makes locks unlock.

Plastic Man solves the case.