Graphic Packs are user generated content, which replaces the default clipboard-style vehicle icons with other graphics, some are animated. You can enable/disable them from the game menu, clicking on "Profile" and "Graphics Packs" after that. The files used should be using the format of JPEG or PNG and can be up to 1MB in size.
 
Graphc packs can be uploaded by players with the rank "Fire Apparatus Operator" and above.
 
Each graphic can be no larger than 1 MB and 200 x 200 pixels.