Science Museum Strength Ball-£7.89 was £9.89 Save £2.00
Science Museum Strength Ball.
•The most enjoyable way to exercise and strengthen your hand-grip and forearm.
•Switch on the LCD Revometer, and using the pull cord provided, spin the internal gyro.
•How many revs can you build by spinning your wrists? The record stands at over 14,000 RPM!
•As the revs build so does the torque, making it a real challenge to control.