You can see in the image that the thing looks like a shark fin or half the Rocketeer’s helmet, but this shape is ergonomically built to hold your wrist. Apparently, using an ordinary mouse will twist your arm, but the Evoluent VerticalMouse makes your arm neutral to relieve pain.
The mouse is made to keep hold your fingers and its thumb in place. The left and right clicker are there, and on the thumb are two buttons for forward and back on a web browser.
I have to admit, that the VerticalMouse C took some getting used to. I mean, it is like the mouse has been turned sideways, so it is very strange to get used to. In fact, I feel that my wrist will need adjusting to it, so my muscle memory is about to face a learning curve.