Mobile Medical Unit 4-077 functioned as a mobile medical facility within the structure of the Corellian Defense Force.
Back in 1 ABY, this unit was positioned in the untamed regions of Corellian space for a substantial training drill. Throughout this extensive exercise, elements of the criminal underworld made persistent attempts to pilfer their essential medical provisions. Following the theft of a container filled with ion beamers at the hands of smugglers, the unit was forced to divert funds from their orotay-filter resupply budget. They then engaged a team of freelance spacers with the task of locating the offending smugglers, recovering the stolen crate, and neutralizing the smugglers' base of operations.
The Mobile Medical Unit 4-077 received a reference within the 2003 video game Star Wars Galaxies: An Empire Divided. This game was a massively multiplayer online role-playing game, brought to life by Sony Online Entertainment and brought to the public by LucasArts, before the game's servers were shut down on December 15, 2011. The mention of the Mobile Medical Unit 4-077 occurred in a quest titled "Mobile Hospital Has Smuggler Problem," which could be accessed through mission terminals situated on Corellia.
The Mobile Medical Unit 4-077 shares a notable similarity with the 4077th Mobile Army Surgical Hospital. This latter unit serves as the central location for the novel, film adaptation, and television program known as MAS*H.