Given the DNAS pack mention, this might be a with built-in DNAS patches for specific game servers.
The short answer:
It is very important to state clearly:
: Open USBUtil, select File -> Create game from ISO , and choose your source file and the USB drive as the destination.
You can find archival versions of this software on the Internet Archive or Scribd . USBUtilV2.0FullEnglish_201607 directory listing
. Select your game's ISO as the source and your USB drive's root directory as the destination. Wait for Conversion : The program will split the game into files named ul.xxxxxxxx Play on PS2 : Plug the drive into your PS2, launch OPL (via Free McBoot ), and your game should appear in the USB games list. Important Considerations