Convolution's Cousin ("CC") designed by Stewart Coffin, was Dave Rossetti's IPP34 Exchange Puzzle. It's the "cousin" because it looks and behaves very similar to Coffin's Convolution. Except that this cousin is the smaller cousin, has only five pieces versus Convolution's seven. While I don't have a copy of the Convolution, I do have the Convolution Ball, which is spherical shaped and based on the former's cube design.
The CC is made from African Mahogany. Dave made the puzzle himself under the mentor-ship of Tom Lensch. The mentoring appears to have paid off as the CC is very well constructed with high quality fit and finish. In fact the fit is so good that the join lines of the separate pieces are very well hidden and pretty difficult to find.
This is an interlocking puzzle and the object is to disassemble and re-assemble the pieces. First task of course is to find the "locking" piece that keeps the rest together. Not too difficult as I pushed and prodded and after a short while, figured out how to move the first piece. Once the first piece is sorted out, its a matter of finding which piece comes next and so on. Despite the snug fit, all the pieces slide smoothly and no force is required.
The dis-assembly takes 6 steps and there are two ways to take the puzzle apart; so it would not really count as a sequential movement puzzle. A bit of rotation is also involved in the process. While dis-assembly is not hard, the re-assembly is, especially if you forget the order and orientation of the pieces and how they interact with each other. It can then pose a huge challenge to get it back to the solved state. That's why its always advisable to document the steps with photos as you play.