CERROPI Large Newtons Cradle Pendulum with 7 Balls, Physics Perpetual Motion Desk Toys for Office, Calm Down Fidgets, 50+ Sec Swingtime (Beech Base)

Great quality and fun for all. I hit this for my husband’s office and most can’t pass it without playing with it.

I bought the heaviest of the versions, the marble base one. The solid weight of both the base and the balls results in the balls staying in motion for a good long time. It's a lovely piece that would make an elegant addition to any desk.As stated in other reviews, the main problem is tangling. Young kids in particular will find it irresistible to try wild combinations of moves that will inevitably result in tangling. Therefore I wouldn't really recommend that you give this to a child under 12 as a toy unless you are going to supervise or you don't care if it becomes broken.If you have a tangle I recommend immediately flipping the unit upside down, preferably with a second person's help so that the balls do not further tangle or knot. In the upside down position you may be able to untangle the knots if the tangle isn't too bad.If it is too bad, get a thumbtack or a sturdy pin and a hammer (as recommended in the ball replacement directions) to detach one of the strings. Push downwards if the unit is upside down (or upwards if right side up). This will push out the small cylindrical plastic wedge that holds the string in place and release the string. (Don't lose the wedge!) With one string free it should be easier to untangle the threads. To replace the string, turn the unit right-side up, place the string through the hole (placing the string about a millimeter past the top seems to work well) and tap the wedge back in place with a small hammer or other solid object. You may have to try more than once to get the ball hanging at the proper alignment. (This is also the basic procedure for installing the replacement ball.)This is not a lot of fun, but it will fix the tangle. But the best plan is to be careful and not let tangles happen in the first place.

I purchased this Newton Cradle Balance Balls set for my husband. He’s had it for over a year and is very happy with it. The quality is great. It is very sturdy. Would recommend.

nice, heavyweight base. The whole family enjoys it.

Purchased as a present for a respectful 10 year old boy. After about 10 uses the outermost ball's line broke (thank goodness not an interior ball). The ball remained attached to the other side via the intact line. He has continued to play it for about 1 year with hundreds of plays and the remaining lines have stayed intact. I am ordering another for his friend who loves to use it when he visits. Overall, it's probably about the best quality one can expect, but just beware that breakage can and does occur.

After reading reviews of other Newton’s Cradles, it seems like a common problem is that the balls don’t swing back & forth for very long. This cradle however, does not have that problem, as it goes for about a minute & a half with one release. I’m guessing the 7-balls (vs most cradle’s 5 balls) makes a difference.We got the wood base model and are very pleased with it’s sturdy quality and it’s simple but attractive look.Take note, do not release the first ball from too high otherwise the balls/strings can get tangled, which can very easily and quickly dissolve into a knotted mess. Fortunately, the customer service at CERROPI is proving to be fantastic bc my son did, indeed, release from too high and the balls got tangled. CERROPI support immediately responded and tried to help me fix it myself but then quickly offered a replacement (I wouldn’t recommend counting-on the same outcome if your balls/strings get tangled). As someone who feels like decent, let alone fantastic customer support is a very rare thing these days, I am very pleased and grateful for the response I got from CERROPI.I would DEFINITELY recommend this Newton’s Cradle for anyone looking for one. I was hesitant to spend a little more bc there are definitely less-expensive ones out there, but I doubt the quality is nearly as good with the cheaper ones, and I’m very glad I spent the extra money to get this high-quality cradle, not a cheap, plastic one.

Birthday gift for family member who wanted this specifically!Perfect gift!

The media could not be loaded. We bought a granite base. Heavy, solid, stable. One ball goes for 40-50 seconds. Lots of different patterns can be performed. My son is happy!