The Fraction Cubes set comes with sixteen pieces, including one nesting cube and fifteen coloured blocks in a whole, halves, quarters and eights. The blocks can be used for building and stacking, or for exploring basic fractional relationships. The pieces are made of solid rubberwood, and the finishes are water-based stains which will not chip or flake off. The large nesting cube measures 5 cm (about 2") per side.