Auto-Start NSD Rainbow Lit Spinner Gyro Ball – Up to 15,000 RPM Premium hand strengthener and wrist exerciser for grip strength training, forearm workout, and pain relief; durable and portable

These are worth the money! After trying the cheaper, string-wound spinners, which ultimately were WEAKER in their resistance and a pain to string-up, I watched several Youtube videos and decided to spend the money on something I'd truly find to be a good quality Spinner. This is it! Not only with an easy, auto-start mechanism, but the resistance builds as high as I can go with my strength, and I love the flashing light colors. I did have 1 that stopped working after a short period of time (1 month from purchase), but so far the replacement is working fine (after 2 months of purchase).

Bought this to help exercise my wrist and forearm after an RSI scare.Not gonna lie. I spent a few hours figuring out how exactly to spin this, until enough videos made me realize that I had to spin it slower and not faster - I was spinning too fast to stay in sync.The key for me was the wrist motion (can't really explain it, but you should be rotating it horizontally and tilting it on the vertical axis) as well as trying to "feel" it sync.Once I got it working, I couldn't resist using it even when tired - there's just something about the flashing lights and the whirling and the resistance and the motion that just feels rewarding. I'm pretty sure the flashing lights are a way of gamifying it - which is a really good thing if it gets you do something that helps you.I bought the auto start model because I knew I would lose the rip-cord of the other models, and while I didn't get a counter, after a week with this I decided to get one to keep track of how well I'm doing with it.Did it cure my RSI? Too early to tell.Is it a great exercise? HECK YEAH

Works great, feels good, and I could tell the difference in my grip within a few days of having this product. Starting to make grinding noise but these things wear out. Still works perfectly however.

I love this. It is essentially a gyroscope. The ball contains an inner ball which is weighted and rests on gimbals You don't need a string to start it. It has an internal spring. Once wound up, the ball beings to turn, By rotating your wrist in a particular way best learned by viewing a video, the speed of the ball will increase. As the ball increases in speed, the laws of physics dictate that attempting to rotate its spin axis by applying torque, the gyroscope will try and rotate at right angles to the force you apply. This is called gyroscopic procession. This is why gyroscopes are used in navigational systems on earth and in space. They want to stay in position and by so doing, there is an initial frame of reference.As the speed of the gyroscope increases it gets more and more difficult, that is you need to apply more force to get the ball to spin faster. As a result you are putting stress on the muscles of the wrist and forearm...exerciser. It is a novel way to strengthen your arm and is just plain fun. I recommend you also purchase the NSD Power SM-02 Precision Multi-function Speedometer so you can measure how fast you can get the gyroscope to spin.

Enjoyed this immensely - while it worked. For some reason where it was initially easy to start up, it is now impossible. Can get it spinning but it won't engage enough to accelerate.There isn't many areas for this to fail and it appears to be all in order - in general it appears "like new". Rated a 0 for durability - just using it as it was designed. Stopped working.Just be aware that for $40 you may not get much life out of it... YMMV.

It took a little while to figure out how to get the ball to spin up, but after watching the online video I quickly caught on. I bought this to help strengthen my wrist after recovering from a torn tendon in my thumb and wearing a brace for five months. Once spinning it takes very little wrist movement to keep it going, strengthening comes from resisting the natural movement of the gyroscope. It quickly goes to work on the wrist and forearm. I had looked at these for years with curiosity and a bit of skepticism, but now that I it has helped my wrist recover I'm a true believer. Great product?

I bought this because a friend had a similar model. This one is good for the money, and is great for getting started with these to see if you like them before buying something better made. I used it for a few weeks before the bearings started to wear, and you can really hear things starting to wear out inside.It still works, but needs a bit more to get it going than it did before. I wish I would have gotten the one with the counter on it instead, cause I'm a fan of seeing stats on things.

I ordered this for a buddy of mine who has been undergoing treatment (chemo and radiation) for a brain tumor. He's not doing well at all and has lost a great deal of strength in is hands, arms and wrists. This device is actually helping him, which is all I could have hoped for. This nice thing about this device is that it works well at even slow speeds. You don't have to crank it up very high to get some resistance, which is perfect for my old buddy (he's 86 years old).I highly recommend the NSD Roll 'N Spin if you want or need a minimal fatigue hand and wrist workout, whether you're recovering from an injury or you just need to build up your strength slowly/gradually. You CAN speed it up and get a workout if want to, but at lower speeds it perfect for someone who just can't handle heavy loads. HIGHLY recommended.