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This product is no longer available, but don't go just yet.


  • Easy-grip outer sphere allows increased control and prolonged usage
  • Variable resistance is achieved by increasing or decreasing the speed; therapeutic for hands, wrists, arms, biceps and triceps
  • Aids in the prevention of repetitive stress injuries and carpal tunnel syndrome
  • Get the edge in rock climbing and any other sport that requires control and a strong grip
  • The faster the unit runs, the brighter the lights will be until your whole hand is engulfed in a bright glow
  • Generates up to 32 lbs. of gyroscopic pressure when maximum RPMs (13,000) are reached


View all Dynaflex Hand Strengtheners

REI membership


Best Use Climbing, Rock Climbing
Material(s) Plastic
Weight 9 ounces

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We stand behind everything we sell. If you are not satisfied with your REI purchase, you can return it for a replacement or refund within one year of purchase.

REI's guarantee doesn't cover ordinary wear and tear or damage caused by improper use or accidents.

If your item has a manufacturing defect in its materials or workmanship, you can return it at any time. See our limited warranty.

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