Hand Muscle Developer
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Hand-gripper,It is also named stress ball and vent ball.It is popular in the Euramerican fitness ball.It is made of the high elastic material.
The main shape is round and egg shape. It is pliable when we hold it in hand.This fitness ball is suitable for all ages to exercise the brawniness
and flexibility if the fingure.The key important is to use it for the person who are suffering operation to recover body