A small electronic surveillance device designed to track both friendly and enemy agents in Goldfinger. In order to follow “the man with the Midas touch” (Gert Fröbe) to his Swiss base, Bond (Sean Connery) plants one of the magnetic homers in Goldfinger’s Rolls-Royce. The signal is then received on an audiovisual panel built into the dashboard of 007’s Aston Martin DB5. Its range is 150 miles.

A smaller homer is standard field issue and is fitted into the heel of James Bond’s shoe. This device allows the CIA to determine that Bond has been captured by Goldfinger and transported to the United States on a private jetliner headed for Friendship Airport outside Baltimore. In order to alert the CIA to Goldfinger’s plan to detonate an A-bomb in Fort Knox, Bond removes the homer from his shoe and places it in the suit pocket of mafioso Mr. Solo (Martin Benson), who is supposedly headed to the local airport for a trip to New York. Unfortunately, when Oddjob (Harold Sakata) murders Solo and completely crushes his Continental, the homer is destroyed, and Felix Leiter (Cec Linder) is unable to receive the message.

In The Man with the Golden Gun, Bond (Roger Moore) employs a similar audiovisual receiver in the cockpit of his seaplane when he tracks Mary Goodnight (Britt Ekland) to Scaramanga’s remote island off the coast of China.

The idea of a homer and its audiovisual tracker in 007’s Aston Martin presages the development of GPS—now a staple in all modern automobiles and smartphones.