4-LOM was originally a protocal droid created to serve the passengers aboard te Kuari Princess space liner, however 4-LOM took up a more challanging job, stealing the passengers' valuables.  When a careless passenger took aboard one of the most valuable gems in the galaxy, he took it and no one suspected him.  Later, thanks to an upgrade from Jabba The Hutt, he became one of the few droid bounty hunters.  Jabba paired him with the Gand findsmen known as Zuckess, the Uncanny One.  From which 4-LOM hoped to develope an intuition.  The two earned fame in the bounty hunting circles because of thier superb work.  After Zuckuss suffered a life threatening lung injury, the two picked up a bouny for the Rebel Alliance to pay Zuckuss' medical expenses.  However, the capture of Governor Nardix made them unpopular with The Empire.  They hoped to patch up thier relationship with The Empire by exepting Vader's bounty for Chewbacca and Solo.  For a while they played double agents trying to get Solo's carbonite slab.  While in an epic battle aboard Slave I  Fett blasted him to pieces.  Zuckuss repaired him, but he was never the same.  He was ruthless carrying out assignments for clients like Quaffug The Hutt.  He teamed with Zuckuss for a short time, but worked alone for the most part.