"Your Highness, there's nothing more we can do tonight. The shield doors must be closed."
―Major Bren Derlin[src]

Shield doors were employed at Echo Base to seal the interior of the Alliance to Restore the Republic base from Hoth's sub-zero temperatures. Shield doors were used widely throughout the galaxy. Created by the inventors of the Hush-98 comlink, this technology was reliable, and took up very little amounts of energy to run, making it very efficient.

The Shield Doors used a thermal-capturing technology that allowed heat to be built up and distributed throughout Echo Base.