Green Lantern ring

A Green Lantern ring is a piece of jewelry created by the Guardians of the Universe. It is used by members of the Guardians' galactic law-enforcement agency, the Green Lantern Corps. The ring is imbued with energy derived from the Central Power Battery of the planet Oa. By charging the ring before the battery, and reciting the oath of the Green Lantern Corps, one can perform a variety of fantastic feats. The ring generates green energy, which can be shaped into a solid light constructs of any design. The only limitations in terms of this is the limits of the wielder's willpower and imagination. However, a Green Lantern ring does have one additional vulnerability. Its energy is ineffective against anything that is yellow in color. Hal Jordan, a human member of the Green Lantern Corps, and protector of Sector 2814, wields a Green Lantern ring.