Ptolemaios is Celestial Being's (CB's) tactical mobile suit (MS) carrier. Like all CB-built units, it's reliant on GN Particles, however, it doesn't have its own GN Drive. It instead taps into a large internal particle storage tank that's periodically recharged by a Gundam's GN Drive. Because Ptolemy wasn't made to be a warship, it has no built-in weapons. While it may not be formidable in combat, it has its own defense systems and equipment to operate and survive in combat situations.

Externally, Ptolemy was built with a large rotatable peripheral docking ring. The ring itself has 4 docking ports. Each of the ports is docked with MS Containers that contains units GN-001 - GN 005. Ptolemy was designed to be compact and economic of its size, therefore the Gundams utilize only a single linear catapult (an MS launcher that uses magnets). The catapult's opening is on top of Ptolemy. Whenever a Gundam needs to sortie, the docking ring would rotate the specific Gundam on top and slide it down from the container to launch from the forward ship hatch.