Adjustable Finger Strengthener and Hand Exerciser - with BONUS 4K Ultra HD eBook Our finger exerciser provides wide range of tension for strengthening grips and fingers Strengthening your wrist , grip and fingers is important for musical instruments like guitar and bass Adjustable from 3.5 to 6 lbs of resistance for the perfect workout Increase agility , dexterity , and mobility with our finger and hand gripper equipment . Makes great gifts and accessories for musicians or rock climbers The best physical therapy rehab techs use this finger strength trainer for stroke recovery , arthritis relief , and surgery recovery