Antigravity plate

Antigrav Plates are technology invented by the UNSC. As of 2531, they were old technology, and they never quite panned out, but some were still around. What exactly they were intended to be used for was never specifically stated, but it is possible that they were to be used to lift heavy ordinance by causing it to float.

In 2531, the United Rebel Front acquired one of these and used it in an elaborate attempt to capture a team of Spartan-IIs. With a focused beam from the plate, the MJOLNIR Armor sensor systems were tricked into thinking they were in a ten gee environment. The armor increased internal pressure and rendered them unconscious, allowing the rebels to capture them with Neural Inhibitor Collars