Double Layer Pentominoes 3D

The Pentominoes contain 12 pieces, each consisting of five squares joined edge to edge forming different shapes. You may find the shapes of the alphabet letters: I,L,P,T,U,V,W,Y,Z. The letter "F" looks like it had an accident and "N" takes a little imagination.

If you think building blocks is kid's stuff, try to build this square (as well as many other shapes). The Solid Pentominoes offers a great challenge to any puzzler!

Object: Empty and re-pack the (approx. 4.75 x 4 x 1.75 inch) case with all of the pieces. Build geometric patterns and pictures outside of the wooden case.
Difficulty: Very challenging!