Power ring

 are the signature weapons of the Green Lanterns.

Capabilities
So far, the rings have demonstrated the following capabilities:
 * Flight: the ring allows every user the ability to fly.
 * Force field projection: every ring can provide a force field around every user as a shield.
 * Construct creation: every ring allows the user to create any known solid object in a green aurora.

Known users

 * Hal Jordan
 * John Stewart
 * Alan Scott