Approximate Dimensions: 3.5" x 3.5" x 3.5"
This is one of the most difficult packing problems that you'll find.
This crafted wooden brain teaser cube contains 25 identical Y shaped pieces. The objective is to build a 3X3X3 Cube, using all the pieces.
You can also try building other rectangles shapes by using part of the pieces.
It comes with a nice looking base and a lid for keeping the pieces all together. Consider to be one of the hardest cubes ever.