The puzzle [A] .. [D] are from the private collection of Mr D. Gebhardt.
[A] .. [C] have a quite poor mechanism. They are really just a collector's item.
Puzzle [D] has a plastic clip instead the typical metal ring. Besides it has a significantly
better quality and turns very smooth. Shape and material are different, too.
While [A] .. [C] are of the same type and seem to snap into place at a proper position (at least a little bit), [D] doesn't offer this feature.
[A] white, yellow, black, pink
[B] white, yellow, black, transparent blue
[C] white, yellow, orange, transparent blue
[D] white, yellow, red, blue
Size: ca. 4,5 x 2 cm without keychain
Weight: 17g with keychain [A], 12g without chain [B][C],
From the 4x4 Cylinder keychains the small Varikon Tower should be preferred instead!
See also: Varikon Tower, Babylon Tower or Whippit for more keychain puzzles of this kind.