Specifications:ABS+Metal alloySize: 7 * 7 * 6cmPacking List:1 X Fitness Gyro1 X Rope1 X Storage Bag1 X InstructionsHow to use:1. holding the wrist ball with one hand, the opening part of the upward, the other hand will be the head of the rope into the hole in the center of the ball.2. with the thumb of the hand holding the ball, turn the ball forward, the rope tightly wrapped around the center of the ball in the center groove.3. when the rope around the center of the ball half a circle, stop turning the ball center. Use one hand to hold the ball, the other hand to pull out the rope quickly and let the ball center rotate at the fastest speed.4.immediately open the part down, with the wrist part of the ball, until you can feel the speed of the ball can continue to accelerate.Attentions1.DO not drop the ball on hard surface at any time,the heavy rotor will damage.2.DO not touch the ball rotor when it is spinning at high speeds,it will burn.3.Do not press the ball core down hard to avoid the violent shaking after starting, which is very easy to cause damage to the ball orbit. The irreversible damage will directly feedback to the change of feel and sound.4.Do not put any lubricating oil into the ball core, this will reduce the friction, which will directly lead to the wrist force ball can not operate.