Abyssal Class GUs- Purely experimental, most don't make it past the testing phase due to the massive amounts of energy required to keep them active, currently the only  Abyssal Class GU active is Black Moon.

Solar Class GUs- Standard combat GU, they are the most common and widely used as they can fulfill any role needed, over 100 units currently are in active duty.

Terra Class GUs- Purely support based GUs, they are less common than the standard issue Solar Class, but more common than the Experimental Abyssal Class, currently 30 in active duty.

Luna Class GUs- Stealth Based they rarely are used in any combat and are mainly used to transport important individuals away from combat, currently three are in active combat with a further 37 used for VIP transport.

King Class GUs- Personal units for important figures in the military such as admirals and generals, they are often outfitted with whatever the person requests, and as such have no standard design, currently 6 in active duty.

Micro GUs- Smaller more compact GUs made for transport of heavy loads and small scale war, over 10,000 have been manufactured but only 2000 are used in the military.