A friend of mine has a Balzee pocket ball washer and I was planning on buying one until I saw this similar product for about the same price that seemed to be more self-contained than the Balzee, which basically opens completely and then folds in half when done.The Go Pocket ball washer is a small pouch made from neoprene, like a can cooler. It is lined with a non-removable microfiber towel pouch that is sewed to the neoprene outer cover around the opening, but the other, closed end is not attached, so one can pull the towel pouch inside out and pull it out (but not remove it) from the neoprene cover for wetting or for washing the dirt out of it.This ball washer is small enough to fit completely unobtrusively in my shorts pocket but is easy to grab when one is on the green. Insert the ball, squeeze and rub the ball inside the washer, and in only about 10 to 15 seconds, you will have a clean ball that is as clean as any you have run through a golf course stand ball washer next to the tee box. I was surprised that it worked so effectively the first time I tried it - I went out to my garage, rummaged in the bottom of my golf bag for an old ball I had found on the course, came up with one that had mud and dirt caked on at least one to three years old, yet it came out completely clean. I used it at least a dozen times in my round yesterday and it stayed wet the whole day and performed flawlessly.I believe that reviews here on Amazon should be objective - they should discuss both the pros and the cons of every product. I'm actually having a tough time coming up with any negatives for this ball washer. About the only one I can think of (and this is a guess since I've just used my Go Pocket only once) is that it has only a moderately durable construction and seems like it would wear out after a few seasons - I'm guessing that for my use (I play about 20 round season) it will maybe last 3 years. If it proves to be less durable than that, I'll come back and edit this review accordingly. A lifespan of roughly a pair of golf shoes is not bad, though, for an item that cost no more than a medium popcorn at a typical movie theater, and this product is clearly not intended to last a lifetime, to be passed on to one's children.I had a few concerns reading some of the other reviews that were more critical of this product. Those concerns turned out to be altogether non-issues and I think are attributable to user error or excessive nitpicking.First, the opening on the Go Pocket ballwasher is not too narrow or tight. The ball fits easily inside and is not at all difficult to remove - one simply squeezes from the closed end of the ball washer toward the opening and the ball comes right out. I would say that the opening is the ideal size, large enough to allow for easy insertion or removal of a ball, small enough to retain water inside without leaking or drying out (slight problems on the Balzee - this is where the Go Pocket's design is superior to that of the Balzee).Second, the Go Pocket does not, contrary to what a number of other reviews have said, leak in one's pocket. If you held it under a tap and filled it or guessed at a few tablespoons full of water going into it, then haphazardly tossed it in your pocket, sure, it will leak, but you also didn't use the product properly. To use, pull the microfiber towel liner out of the neoprene outer case, wet the towel portion carefully with lightly running water without wetting the outer neoprene cover, then squeeze out the excess water but don't quite wring it out. Push the towel liner inside without spilling. Put it in your pocket with the opening facing up. I had no problems with the opening shifting downward or spilling in my pocket - the rest of my pocket stayed perfectly dry.Conclusion: This product works exactly as advertised, it is easily pocketable, it does an excellent job cleaning even dried and hardened mud and dirt off a golf ball, it stayed wet for an entire 18-hole round (I'd bet it would still be wet enough for a 36-hole day), and it did not leak. At no more than the cost of a cheap beer-and-hot-dog combo at the 9th hole turn, it is a very solid value. I give this product 5 stars.