Neelie was a pair of container transports used by the Galactic Empire during the Zaarin insurrection.
They were part of a minor convoy that was "leaked" to rogue Grand Admiral Zaarin, claiming to be carrying Missile Boats. In reality, they were carrying munitions. Zaarin, however, learned that it was a trap and sent only a minor force to destroy the convoy rather than capture it. The attack failed, and the two container transports jumped into hyperspace.
Behind the scenes
The transports appear in Star Wars: TIE Fighter in Battle 11, Mission 3. The briefing states they are carrying munitions. In the game, their cargo says "Miss. Boat," suggesting that they do carry Missile Boats.