Locator chip implant

From The Stargate Omnipedia

Homing beacon given to Stargate Command and Atlantis personnel, allowing them to be beamed out of unfriendly territory by the Asgard transporters installed on Earth's battle cruisers. The tiny device is implanted subcutaneously, making it more difficult for hostile forces to locate and confiscate.

The implant was developed after the larger locator beacon was separated from Stargate Command personnel and so failed to do its job.


Off the Grid - SG-1 is the first unit to be given locator chip implants.
The Scourge - Because of the planet's unusual magnetic activity, SG-1 is unable to be detected on the surface of Gamma Site by the Odyssey.