Class-2 Energy
From Halopedia, the Halo wiki
The Class-2 Energy[1] is a Covenant class of vehicularly-mounted energy weapons.
They see widespread use, and two such weapons are mounted on the Shade turret and the Banshee fighter. Three are equipped on the Phantom dropship for point-defense.
Plasma weapons of this class are very powerful agaisnt ground forces and lightly armed vehicles.