I had owned a pair hand grippers when I was teenager and I didn't get much use out of them. The pair had a 5-pound resistance each,and I thought of them as more of a novelty at time.
Last week, I was sent a Hand Gripper set, which contains a pair of wrist wraps and one adjustable hand grip.
The wrist wraps have a loop that your thumb will slip into; then you wrap the rest of the material around wrist and fasten down with the attached Velcro. The wraps are used to protect your wrists while you're lifting weights. You can also wear the wraps for cross fit, kickboxing, cardio and other workouts.
The Hand Gripper can be adjusted from 10 kg to 40 kg (2 lbs to 88 pounds). It is used to help gain (or regain) strength in your hands.