Aris Boch's tracking device
From The Stargate Omnipedia
Portable unit used to locate assailants and targets of Aris Boch, attached to an armband on his shoulder. The device completely relies on Goa'uld technology to track targeted subjects. In the event the target is no longer carrying Goa'uld materials, it becomes useless.
KEY EPISODE
Deadman Switch - When Korra informs SG-1 that Aris is tracking them with Goa'uld technology the team discards all Goa'uld devices, making Aris lose track of their whereabouts.