Kon Garat disabling drones
From The Stargate Omnipedia
Cylindrical units vital to stage one of the Loop of Kon Garat, an annual space race held in orbit of the planet Hebridan. They are powered with maneuvering jets and can give chase to any vessel within their sights, and fire green, plasma-based weapons at ships until their shields disengage, disabling the vessel. The drones are incapable of destroying a craft, but simply fire upon it until it is no longer a viable contender in the race.
KEY EPISODE
Space Race - Drones take out several ships in stage one of the 59th Loop of Kon Garat, including the Tritan.