Helps develop isolated finger strength, flexibility and coordination. The ergonomic ball shape positions fingers and hand for ideal pressure distribution. Cando Digi-Extend 'n Squeeze™ provides complete reciprocal exercise program (flexion and extension). Available in different colours for different strengths: Yellow, Red, Green, Blue, and Black. Four Colour-coded extension bands accommodate lightest to the heaviest requirements. Comes with exercise pamphlet.