Activation Index

The Index is vaguely T-shaped, with a faint green or blue glow emanating from a stripe on each side. The object seems to be merely a digital storage device containing the software or access codes needed to activate the rings. Each Index is stored safely within an Index Chamber, a large room that is located at the core of every Library on each Halo installation and guarded by waves of Sentinels. 

Notes: The activation index is roughly 11.9 inches long, and has two functions, to activate a Halo rings life destroying weapon, or to activate the rebuilding of life after.