With some special edition (like 50 or 100), the CFF booklet comes with some puzzle(s). You need to be member of NKC which entitles you to receive some booklets with puzzle news and analysis inside.
Several puzzles competed and a choice was made regarding the price of the puzzle, its shape (to be mailed easily), the design (which ideally would incorporate the words "CFF", "100", "2016").
The puzzle chosen was designed by Michel van Ipenburg and crafted by Robrech Louage out of trespa and is a n-ary puzzle, meaning that you have a sequence of repetitive moves to progress on your puzzle journey. Not being a professional of n-ary puzzles, I have not yet recognized the precise pattern. But don't worry, this is not a difficult puzzle and does not requires thousands of moves. So it's perfectly suitable for all puzzlers!
The goal is disassemble the 2 disks and then reassemble them so that you can see the 3 words written through the 3 holes.
I must admit than being new to this kind of puzzle I was also naive and it appeared that it was super easy to disassemble the puzzle because the maze looked like the same, so in very few moves it would be ok. But actually it is not the case! So when it seems that you can move a bit but not completely a pin, don't use force at all, it's normal and you will have to make some more moves to progress.
I must add something: this is a limited edition of 500 and no other will ever be made, so take care of it even if it won't be the most expensive puzzle in your collection :-)
As you can see, the 2 disks are attached with a small scotch tape which allows not to be spoiled, and it does not (actually for mine) leave any sticky marks.
There was another small surprise: another puzzle, very easy, but still nice designed by Roland Koch:
The goal is to let the puzzle how "CFF" and "100" on both sides by rotating the 3 disks. First you need to open the black button and rearrange the disks as mention in the instruction and next solve it.
I whish to have received all the puzzles that were compete with each other to be shipped with this special edition of the CFF booklet, but well, I also did not expect to receive any puzzles, so I was very pleased to received 2 puzzles!