"Tales from the Rings" contains supplemental material set in the universe of "ΔV: Rings of Saturn". This free DLC currently contains:

e-books

• "Howling at the Stars" by Eric Eshleman (pdf)
  
• "Tales from the Rings" by Eric Eshleman (pdf)
  
• "K37 TNTRL Operation and Service Manual" - an Digital Artbook (pdf)

graphics

• 6 original 4K-resolution wallpapers.
  
• 256 character avatars you can use anywhere you want.

other assets

• cellphone wallpapers.
  
• ringtones.
  
• templates for custom in-game ship paint.
  
• 3d models of the ships.
  
• crew portraits.
  
• seamless animations for streaming and desktop background.

You can find all the files of this DLC in your game directory, under tales-from-the-rings subdirectory.