Here are the X, S, U and Z pentacubes, left as natural wood colour
P, L R and V pentacubes are stained "rosewood" (R is sometimes labelled "F")
The I, T W and Y pentacubes have been stained "mahogany" for contrast
The U-pentacube will encircle another piece so its gap must be very exact
The 12 pentacubes can be assembled into a block. Start with W, Y and Z
Add the X-pentacube, standing upright on the left