A microthruster was a type of engine manufactured by Corellia StarDrive around 3999 BBY. They were found on the pirate ship Marauder Starjacker.
Koensayr Manufacturing also produced the N2-f microthruster, used on the prototype StarViper-class attack platform Virago, personal starfighter of Black Sun's Dark Prince Xizor.
Sources
Star Wars Customizable Card Game — Premiere Limited Card: Ubrikkian 9000 Z001 (backup link)- The Essential Guide to Vehicles and Vessels (First mentioned)
- Shadows of the Empire Sourcebook
- Tales of the Jedi Companion
Star Wars Action Fleet (Pack: Virago) (backup link)- Gundark's Fantastic Technology: Personal Gear
- Strongholds of Resistance
- Star Wars: X-Wing Second Edition — Scum and Villainy Conversion Kit Card: Black Sun Assassin — StarViper-class Attack Platform
- Star Wars: X-Wing Second Edition — Scum and Villainy Conversion Kit Card: Black Sun Enforcer — StarViper-class Attack Platform
- Star Wars: X-Wing Second Edition — Scum and Villainy Conversion Kit Card: Dalan Oberos — M12-L Kimogila Fighter
- Star Wars: X-Wing Second Edition — Scum and Villainy Conversion Kit Card: Guri — StarViper-class Attack Platform
- Star Wars: X-Wing Second Edition — Scum and Villainy Conversion Kit Card: Prince Xizor — StarViper-class Attack Platform