It looks like any old trackball mouse, complete with a bulbous ball.
Like its wired counterpart first introduced in 2009, the SlimBlade Trackball, Kensington's new wireless trackball has programmable buttons.Unlike trackball mice with a ball controlled by the thumb, the SlimBlade Pro's twisting globe is meant to be used by any digit and either hand.But if you've never used a trackball mouse before, you may find the SlimBlade Pro's operation more difficult than something like the Logitech MX Ergo, whose shape is more similar to a traditional mouse.
The SlimBlade Pro Trackball is currently selling for $120, just a $10 premium over the wired version's MSRP.