<span class="SFPTagline"> From SCIFIPEDIA </span>

On the series Stargate Atlantis, an Ancient personal shield emitter is a technology developed by Ancients of the Pegasus Galaxy. The device is a palm-sized round object that glows green when in operation. It attaches to the users clothing and envelops the body in an energy shield that resists all attempts to penetrate it protecting the user from harm even from falls from great heights. The device was first seen in "Hide and Seek" and used by Dr. Rodney McKay. Though air easily passed through the shield a flaw was quickly discovered as Mckay realized he was unable to eat, drink or relieve himself. He was also unable to remove the device. The device is controlled by thought and can be used by anyone with the ATA gene. McKay stated that the device imprints on the user preventing another user from operating it once it has been activated. However, in the episode "Irresponsible", John Sheppard was able to use a personal shield device previously operated by Lucius Lavin. Lavin also appeared to have better control of his device allowing him to eat and remove it at will.