Op Mus was a BFF-1 bulk freighter that had been assigned to carried food during and after the evacuation of Yavin 4.

However, while in transit it malfunctioned and was stranded in deep space. After the loss of the Dobll freighters, the Rebel Alliance could not afford the loss of yet more supplies. So the Delta-class DX-9 stormtrooper transport Jaamn was sent to repair the freighter. Red Squadron, including Keyan Farlander, was sent to oversee the repair process and protect it from encroaching Imperial forces.