Kensington Pro Fit Ergo TB550 Trackball Mouse, Rechargeable Battery Included, Bluetooth(LE) & 2.4GHz Wireless Connections, Ergonomic Design, 4D Scroll Wheel, Charcoal Blue (K72196WW) Charcoal Blue/Grey Ball Wireless

I am an IT professional and always on the look for devices that can help improve my posture and office ergonomics. I have previously used flat mouse like the apple slim design mouse types but they are only good for travel as they are portable and not very good for extended use of 8 hours per day. This mouse is ergonomic and very well designed with office workers in mind. The 45 degree angle seems to provide comfortable angle of support and the vertical and horizontal wheel is very useful. The mouse ball comes off easily for cleaning and the mouse itself is nice to hold in hands without any signs of fatigue. At 49.99 it's good value for money.

I wasn’t sure I was going to get on with the Pro Fit Ergo TB550, but I’m hooked and plan to stick with it. It gets off to a good start by being rechargeable and connecting using Bluetooth. No batteries to replace, no annoying dongle occupying a port, although you do get a USB-A dongle, should you need it. It has the all-important side buttons and 4-way scroll wheel with adjustable dpi (they call it 4D but it isn’t 4D; 4-way is much more accurate). And then, of course, there’s the trackball; it’s years since I used one but its presence here adds greatly to the mouse’s versatility. It’s beautifully smooth in action. The ability to eject the ball for cleaning is very welcome too. Best of all, though, is the comfort offered by this mouse. It really does relieve strain on my wrist and hand, my forearm too. Congratulations to Kensington for their use of recycled plastic, even if only 51% (I imagine much more than that could be really difficult). Overall, while the mouse might appear a little pricey, at £50, it really is worth raiding the piggy bank. You’ll never again be content with anything cheaper!

It's a great ergonomic mouse that helps to reduce wrist strain and fatigue. The trackball is very smooth and responsive, and the multi-directional scroll wheel is very convenient. The mouse also has a number of other features that I like, such as the ability to switch between Bluetooth and 2.4GHz connectivity, and the ability to customize the button functions. I also like that the mouse is rechargeable. No more having to worry about batteries running out! And the battery life is excellent. I can go for days on a single charge. It is a well-designed, ergonomic mouse that has made my work life so much more comfortable.

This mouse is great in concept but poor manufacturing tolerances bring it down. The edges were sharp and unfinished and sharp. In the hole where the ball sits, there was a piece of sprue poking out that caused friction on the ball and affected its tracking. The ball also did not roll very freely when starting a movement so it would stick then suddenly jump at the start. Can not recommend.

This review is for the Pro Fit Ergo TB550. Having used a number of Kensington mice and trackballs over the years, I do expect the quality/usability to be superior compared to a lot of stuff out there. This trackball is indeed up to the their usual high standard. After a quick battery top-up (approx. 1hr at a starting charge rate of 213mA), we're good to go. I'm using the bluetooth option for connection. You will need to download the 'KensingtonWorks' (134MB) software to set up your mouse correctly. This is apparent on first use, as the mouse scrolling speed is way too fast and a bit erratic. Once installed, there are lots of options to set your trackball up exactly as you want it. A reboot is definitely recommended so that everything is settled, especially (in my case) the bluetooth connection stability. The hand position is wonderful, just gently resting on the unit, everything is right there, exactly where you want it. No stretching of fingers to reach buttons, the ball right under the thumb, and your hand in a truly natural position. Button clicks are effortless, soft to the touch, but definite enough to reduce accidental clicks. The scroll wheel has deep grooves cut into it, which allows definite scrolling without the slipping I've found with some other wheels. All in all a very enjoyable experience in using this model Ergo TB550, once set up correctly. I have to confess that my absolute go-to favourite trackball is (or was!) an old 'Microsoft Intellimouse Trackball'. I've had 2 on the go for well over 20 years, and kept them running with regular cleaning and maintanance. They are however starting to fail occasionally now, so with some sadness and reluctance I have to find an alternative. I believe this particular Kensington model may well be the answer replacement-wise, so time to bight the bullet and confine the Microsofts to the spares draw (I'm not chucking them... just can't do it!). 5-Stars all the way from me, and would thoroughly recommended, especially if you've never tried a trackball-mouse before.