UK (?) Swift Communications Phonecard

Limited Edition phonecard set in seperate folders by Swift Communications. Just 2000 made.
I have a feeling that there is 12 to a set. Might be more, but not less than 11 I am sure.
I have these 7. They are numbered; 1, 2, 3, 4, 5, 6 & 11.

If you know of any other Maiden cards, or know something else about these cards, please contact me.