YAKAGI Hand Grip Strengthener - Grip Strength Trainer - Finger Exerciser & Hand Exercise Balls. Adjustable Finger Exerciser and Hand Strengthener: Change the positions of the hook to adjust the resistance value, 6 levels resistance( Heavy Black: 13 lbs, 17 lbs, 21 lbs, and Light Grey: 6.6 lbs, 8.8 lbs, 11 lbs), Suitable from beginner to advanced.
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