Antimatter charge

Antimatter Charges are explosive weapons used by the Covenant. They use antimatter charges in a variety of ways. To blow through ship armor during boarding action, or as anti-vehicle and anti-personnel weapons. These appear to be the choice explosive of Ranger Elite teams, as they have sometimes been used to destroy Magnetic Accelerator Cannons on board ships.

Antimatter is extremely unstable, any contact between unstablized anti-matter and normal matter causes an instant, massive explosion of energy. Only one kilo of antimatter reacting with one kilo of matter would yield an explosion of 42,96 Megaton, which almost is equivalent to three Hiroshima-bombs (45 Mt combined)

A larger version of these charges, called Covenant Bombs, are also used by the Covenant to destroy large objectives, such as stations or orbitals.