Building Block Stress Reliever, 3.125″ W x 1″ H x 1.5″ D, Handcrafted polyurethane foam stress balls, due to their handcrafted nature, stress ball sizes, colors and textures may vary. Factory cannot guarantee consistent imprints or PMS matches, not a child’s or pet’s toy. NOTE: while pieces do stack like traditional building blocks, they are sold individually and not as a set.