Gravity lift
From Halopedia, the Halo wiki
Summary
A piece of Covenant technology. As the name implies, it uses artifical gravity to move troops and supplies up and down through levels, or from a ship to the planet suface. Gravity lifts are also used for Deployable Lookout Towers. Gravity Lifts appear as transparent purple-hued cylinders of light. Gravity Lifts are seen twice in the game Halo: Combat Evolved. These scenes both involve the Master Chief and the Covenant CCS-class battlecruiser Truth and Reconciliation, which can be seen projecting the lifts in the levels Truth and Reconciliation and Keyes.
