I know there are alot of series has been released:

Private Gold, Black Label, Private XXX, Private Penthouse,
Superfuckers, Compilations, Matador Series, Private Video Deluxe, Private Movies, Private Film, Private Video Magazine, Triple X Files, Pirate, and Virtualia.

I hope someone could help me give the more information
about the differences among those series.
It will be more helpful if could give the info description for the each series.

Thank you in advanced.

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