Permanently deleting versions

Hi there, 

Welcome to Box Community and glad to assist! 

To delete your file's version history: 

• Open this sidebar and access any file’s version history, navigate to your Box All Files page and do any one of the following:

• Click the version number badge displayed to the right of the file's name. This badge is available only when multiple versions of the file exist.
  or

• Click the name of the file. Box opens the file in Preview mode. Click the more actions ellipsis (…) and then select Version History.
  or

• Click the file. In the top of the file's preview window, click the blue version number displayed to the left of the file's title.

• Each file version also displays with a more actions ellipsis (…). Click the ellipsis to display a menu of actions you can take. Delete a file version by clicking Delete.

Hope it helps! 

This allows the versions to be restored. I want to permanently delete them so they cannot be restored.