uxcell 2.5mm Ceramic Bearing Balls, ZRO2 Zirconium Oxide Ball G10 Precision 10pcs

Huge upgrade for elecom trackball mouse. Replaced the junk balls in the mouse with these and what an amazing improvement

I replaced the cheap 'ruby' bearings in a couple trackballs and the difference is incredible. It's far, far, farrrr smoother. You really don't feel any 'friction' just the weight of the ball. Some misc thoughts:-Replacing them: It's easy. Remove 5-6 screws from the bottom of your trackball. A couple more screws internally to free the bearings. Toss the current bearings, drop these in. Screw it back together. Takes about 10 minutes. Heads up though, Elecom uses a mix of Phillips head and T6 torx screws. Buy a cheap 'precision screwdriver' set if you don't have one already.-Fit: These bearings match MOST popular trackballs. I used this pack to do an Elecom Huge, Elecom EX-G Pro, and a Kensington. (I forget the name of the Kensington, but it's the classic one they've been making forever. Four big buttons, giant ball, you know the one.)The Elecoms benefited hugely. The Kensington, the difference was noticeable, but not dramatic. I'm not sure if they use better bearings or if it's just been worn in by years of use.

Got these to replace the ruby bearings in an Elecom Relacon (25mm ball). The ZrO2 is noticeably more slick than the ruby, but the static friction feels about the same. As a result, the mouse is even more jittery when trying to make small movements. Allegedly the G5 grade is better than G10 in this regard. But the problem should be minimal with larger balls.

I used these to upgrade my elecom HUGE and they are definitely an upgrade. Smooth as ceramic.

These bearings are absolutely essential for the longevity of the aforementioned trackball, and should be bought along with it. If other people you know want to get said trackball, then you can spare them a purchase of the bearings because you will have enough to replace them in two more trackballs. Just be advised that these are easy to lose, so take care when getting them out of their bag and installing them. For that, you are advised to use a microfiber cloth to keep them from rolling around your work surface, and you MUST use scotch tape to hold these replacement bearings in place when reassembling the mentioned trackball. When everything is secured, you should see the bearings remain in position after taking off the tape. You will save yourself plenty of frustration and time.

Reduced the friction from the ruby bearings id say about half with these.

These are better than the ruby “bearings “ in trackball pointing devices, but not as good as the steel bearings

Swapped the bearings on my Elecom Huge. A little bit of graphite powder, and ten minutes of breaking in, and the static friction of my Huge--which was making precision movements basically impossible--is all but gone. If you own an Elecom trackball, just do it.I'll update this review if I manage work up the bearings to drill out the rubies of my Bitra as well.