Koensayr's N2-f microthrusters served as the maneuvering thrusters for the StarViper prototype, known as the Virago. These N2-f units, deployed in pairs at each wingtip and managed by the flight computer, were designed to improve the fighter's agility.
Sources
The Essential Guide to Vehicles and Vessels
Shadows of the Empire Sourcebook (Indirect mention only)
Star Wars: Shadows of the Empire Micro Machines (Pack: Action Fleet Virago) (backup link)
The Official Star Wars Fact File 135 (VIR 1-2: Virago)