The astromech droid simply referred to as R4 was attached to Gruu Funkistann's Jedi Starfighter during MI5's mission to Ryloth in 42 BBY.
While sitting in the Starfighter on Ryloth waiting for Gruu to return, R4 intercepted a distress signal from a ship nearby. The droid quickly relayed the message to Hardcastle's ship the Last Bolt.
Behind the scenes[]
The little droid was created by the Star Wars... 007 Style series creator Dubya Scott.