The Asgard hand device is a device used by an Asgard to remove the Ancient knowledge that had been downloaded into Jack O'Neill's mind after he looked into an Ancient repository of knowledge on P3R-272. The knowledge within the repository was so vast that it could not be handled by the mind of a modern-day human, since they had not yet evolved to that point, and it was quickly overwhelming O'Neill's mind. If the knowledge had been allowed to continue to unfold, it would have resulted in O'Neill's death. Realizing the danger he was in, O'Neill's subconscious mind developed a method to restore him and save his life. After building a device to supply him with enough power and reconfiguring the SGC dialing computer to allow intergalactic gate travel, O'Neill traveled to the Asgard homeworld. There he was met by a group of Asgard. O'Neill was restored, but the Ancient knowledge was completely removed from O'Neill's mind, restoring him to normal. (SG1: "The Fifth Race")