A portable handheld radio transmitter-receiver invented in 1938 by Al Gross while a high school student in Cleveland, Ohio (United States).The device caught the attention of the Office of Strategic Services (OSS), predecessor to the Central Intelligence Agency (CIA). The OSS recruited Goss, who then lead the effort to develop the walkie-talkie for clandestine and military uses. Code-named Joan/Eleanor, the first walkie talkie system comprised a ground unit, Joan, and an airborne unit, Eleanor. The system allowed OSS agents behind enemy lines to communicate with aircraft in a manner that virtually defied detection at the time. See also Gross, Al.