The evolution of the original Kensington trackball has been an interesting one ever since the late 1990s back when it used to be called Turbo Mouse and only came with two buttons!
Fast forward, almost, 20 years the latest version of the Kensington trackball - Pro Fit Ergo - now integrates a 60-degree vertical angle that forces the palm of the hand to face almost perpendicular to the desk, alleviating the discomfort that comes from holding a mouse the conventional way.
The Kensington Pro Fit Ergo trackball is also wireless so, that means one less cord to deal with, which makes it extremely convenient when using the trackball outdoors. Included with the Kensington Pro Fit vertical trackball is a USB nano receiver that allows the Pro fit mouse to be connected to a desktop computer or laptop via 2.4Ghz wireless radio frequency.
The wireless USB dongle is very useful, especially if your computer doesn't have a bluetooth receiver built-in. The Kensington Pro Fit vertical trackball can also be connected via Bluetooth, thanks to integrating a bluetooth 5.0 chip.
Thanks to dual radio frequency and bluetooth connectivity, you can connect the Pro Fit vertical trackball to three different devices. This means, you can can connect the Pro Fit trackball to one computer via the USB receiver and two additional computers or tablets via a Bluetooth connection.
You can toggle between the three connections via the left side buttons almost seamlessly, although there is a 3 second wait from toggling from bluetooth to radio.
There is only a 1 second wait to toggle from Bluetooth 1 to Bluetooth 2 connection. Just above these buttons, you will see three small leds with a wireless and Bluetooth symbols, which correspond to the three connections (USB, Bluetooth 1 and Bluetooth 2).
In terms of functionality, both radio frequency and bluetooth connectivity have their advantages and disadvantages. Both deliver almost lag free operation and are always active but Bluetooth consumes less power then radio frequency connection because bluetooth goes to sleep when the mouse is not in use. In radio frequency mode, the Pro Fit trackball will also go to sleep but only if you have your computer setup to go to sleep.
Radio frequency does provides a long stable range (10 meters) because of the dedicated radio frequency channel created with the wireless dongle. Another advantage with radio frequency connection is that because there is no idle state, you don't have to move the mouse in order to resume the connection like you have to with Bluetooth.
Having both radio frequency and bluetooth on a mouse is really best of both worlds and convenient, especially if you misplace and/or lose the wireless USB dongle. The Pro Fit trackball has the same dual RF.Bluetooth functionality as the Expert Wireless trackball but with better Bluetooth battery life, thanks to Bluetooth 5.0.
That said, the Pro Fit trackball has to be connected to a Bluetooth 5.0 device to enjoy better battery performance. Bluetooth 5.0 is backwards compatible though, so it will work with Bluetooth 4.2 and previous versions.
On the base of the Kensington Pro Fit vertical mouse, you find the AA battery compartment, glide feet, DPI push button, Wireless mode push button, on/off power switch and the ball ejection button, which releases the mouse ball for cleaning.
The DPI button lets you toggle between 400 dpi, 800 dpi and 1500 dpi. The long led towards the front of the ball will flash once, twice or three times according to the dpi mode
The Kensington Pro Fit trackball feels comfortable in the hand, although depending on the length of your fingers you may or may not be able to reach the top buttons comfortably. With a hand length of 19cm or so, you should not have problems reaching all buttons comfortably. The bottom left side of the mouse has these grooved lines, which help to grip the mouse with the thumb.
The concave area around the red mouse ball makes it comfortable for the thumb to sit while operating the ball, which is large and easily to glide on its housing.
Functionally, the Kensington Pro Fit trackball lets you accomplish computer tasks comfortably and efficiently, thanks to the vertical grip and nine programmable buttons, three of which are actuated by the scroll wheel by pressing the mouse wheel down, left and right. The scroll wheel is rubberized with a threaded finish.
The buttons on the Kensington Pro Fit trackball are programmed via KensingtonWorks software, which can be downloaded from the Kensington website. KensingtonWorks is compatible with newer versions of Windows, including Windows 10 (32/64), Windows 8.1 (32/64) and Windows 7 (32/64). KensingtonWorks for Mac is compatible with macOS 10.15 Catalina, macOS 10.14 Mojave, macOS 10.13 High Sierra, macOS 10.12 Sierra and macOS 10.11 El Capitan.
You can program the buttons anywhere you like, essentially remapping the button functions to whichever buttons are more convenient to you. For example, you can swap the position of the left click and right click buttons. If you're a program coder, CAD engineer or program editor, you own it to your hand to find best comfort you can provide and, the Kensington Pro Fit Ergo might just be it!