A Union variable type MS. It is capable of transforming between mobile suit and flight modes. The Flag's primary armament is a linear rifle that fires electromagnetically-accelerated live rounds, while its melee armaments include a sonic blade/plasma blade and optional leg missiles. Furthermore, both its upper torso and lower section can be separated and transform independently.
An upgraded Flag was created to for counter-gundam purposes, the Overflag. The SVMS-01E and was the mobile suit used by Union ace Graham Aker before the upgrade to the SVMS-01X "GN-Flag.
The OverFlag may be inferior to its predecessor in some respects due to the thinner but lighter amour.
The Flag is a high performance mobile suit that is capable of transforming into a high speed jet fighter mode. Both modes are capable of aerial flight with the mobile suit mode providing greater mobility and the jet fighter mode providing greater speed. The Flag's linear rifle can be used in both modes. However the sonic blade used for close combat and the defense rod are limited to use only in mobile suit mode.
The mode the Flag uses for missions is usually selected and set beforehand. However Ace pilots such as Graham Aker have shown that it is possible for a skilled enough pilot to transform the Flag between mobile suit mode and jet fighter mode in mid-flight.