Gravity anchor (Earth-5875)

"I've gained control of the Halo's gravity anchors, Captain. Get our troops clear and get ready."

- - Professor Ellen Anders

Gravity anchors are a technology developed by the forerunners Builders to maintain the inner surface of a Halo ring secured into the superstructure.

History
During the Second Battle of Installation 00, Professor Ellen Anders gained control of the gravity anchors of Installation 04C at its control room, using it to eject a section of the ring's landmass to send all Banished forces and kill them.