# 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.
# The test is to see how many revs you can build by spinning your wrist - 5,000 or 10,000?
# As the revs build so does the torque, making it a real challenge to control.
# Batteries included.