listening device = podsłuch, urządzenie do podsłuchu
Źródło: http://blog.localdemocracy.org.uk/2009/01/21/listening-in-better-than-asking-for-opinions-2/
Źródło: http://blog.localdemocracy.org.uk/2009/01/21/listening-in-better-than-asking-for-opinions-2/