One side only. White or Black.
All the pieces were designed with the smallest wall thickness available which is the WSF. Most of the piece is 1.08mm but were the indentations are the wall thickness is reduced to .7mm.
The head of the Knight is solid.
My original idea was to have the top of the pieces made smooth and polished, while the base is left with a textured finish. The diameter of each piece is 20mm