The Shlangiian were an advanced race.
While examining a spaceship, Chris Cwej wondered if it was of Shlangiian design before recognising it as a Hith ship. (PROSE: Original Sin)
The Sixth Doctor used a Shlangiian power cell and a roll of copper wire to investigate electrical disturbances from the fogou at Lanyon Moor. (AUDIO: The Spectre of Lanyon Moor)