Stress Ball - Available in 5 Strengths, Injury Rehab & Stress Relief - Grip Strengthy Squeeze Training for adults and Children/kids-Set of 5 Resistance. MAKE EXERCISE SIMPLE – These colorful stress relief balls in three levels of progression (15kg-20kg - 25kg- 30 kg and 35kg resistance) can improve finger and grip strength for athletes (rock climbing enthusiasts, fitness, tennis, baseball, boxing, tennis, golf and shooting) and musicians (guitar players, bass players, pianists and violinists).
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