Watch Case Open Ball Friction Ball Watch Case Open Ball Battery Change

It came today and I used it on my Botta Uno 24 quartz… screw on back with no notches. I tried looped duct tape and was ready to mail it in. But the ball was demo’s on line for this specific watch and I took a shot at it. It seemed too slick to the touch but I tried it straight out of the box and it worked great. $7 plus a battery and I saved hundreds over my last authorized service center mail-in. Happy camper!

First thing's first: is there anything special about this rubber ball? At all? Nope. I feel like someone just found whatever cheap rubber ball would work for this purpose, bought a boatload of them for next to nothing, and is reselling them as watch openers for a huge profit. ...and, you know, I'm totally okay with that, because it's still reasonably cheap, and it works. If you've looking to crack the case of an old watch open for the first time, this probably won't do it. Spend another five bucks and get one of the little pin spanners. What this excels at, though, is more frequent case openings. E.g. if you're trying to really zero in on your watch's regulation, you might open it back up a half a dozen times after seeing what kind of time it keeps while on the wrist. As well as opening the more difficult case backs, I would keep a spanner on hand for your final tightenings, too. Even still, this is handy for unthreading or starting slick case backs. And even after tightening with a small spanner, I can open my watches back up with the ball if I press hard enough.

This review is for a OTOOLWORLD friction ball tool ordered 2026-05-16 and received 2026-05-17. I paid $6.21 including free shipping with my Prime membership. The packaging states Made in China. The ball received is a sparkly blue color, was inflated properly and included a standard needle. It's about the same size as a baseball (a little larger than a tennis ball), fits well in the hand and is easy to grip. Oddly, it even has a pleasant odor but for the same reason, I won't be repurposing to play fetch out of concern for possible toxicity. I was skeptical when I first felt it as it wasn't as sticky as I expected but less than a minute later I had the backs off of two Casio watches that have the six-slot threaded covers. I DIY basically everything but most medical and dental so there's a good chance that the friction ball and technique will be useful tool beyond watch maintenance. I presume that it'll be impossible to feel how tightly I re-install covers after replacing the batteries but I figure that as tight as is possible with the ball will be adequate.

I own other case opening tools. I like the concept of having a ball opener to avoid scratches. While it did not work for all my watches, I was able to open approx. 60% of watches I worked on. For the price, it is a good tool to have.

You get what you pay for, I suppose. This thing does not work at all. It’s just an inflatable rubber ball that’s absolutely slick on the outside. There’s no way for it to grip the case back.

It Worked good i'm using it for an old watch.My mom found back in 1987 at a bus stop. It my wannabe fancy watch. I added a little contact cleaner around the rim.Behind it, to loosen it up, popped right off.Great product

It works on a back that is not stuck or tight. I use another tool to break the seal as needed, and then use the ball to unscrew the back. Opposite to replace the back. For that purpose it's good. Just make sure your expectations meet reality.

I have to open my 111 year old pocket watch 2 twice a month, this makes it easy

Works great, why didn’t I buy one earlier.

It works perfect, I can't believe how easy it opened the watch ! I Definitely recommend it !

The product I received was fully deflated, and there is no way to inflate the ball. There are no instructions also about the same. Useless product, never buy

The item was so badly packaged that it was no longer a "ball" but a flat/collapsed contraption. The "ball" is not sticky enough to give good friction with the back case so only loosely tightened watch case backs can be opened.

perfect tool to add to my watch repair kit