Elecom Mouse Wireless Trackball (Thumb) Left-Handed Red Ball 6 Buttons Tilt Function (Horizontal Scroll) Gaming Grade Optical Sensor Black M-XT4DRBK-G Brand: Elecom (ELECOM) Color: Red Ball (Gaming Grade Sensor) Connectivity Technology: USB, 2.4GHz Wireless Features: Ergonomic Design, Tilt Wheel, Multi-function Buttons Movement Detection Technology: Optical Number of Buttons: 6 This is a wireless trackball for the left hand, thumb-operated, with reliable basic performance and unprecedented new features. The sensor that detects the movement of the trackball is equipped with a high-performance gaming-grade optical sensor, and the optimization of the new high-performance lens and surrounding optical design achieves outstanding pointer tracking performance. By adopting a large 2.5mm diameter artificial ruby for the support ball, the ball control feel has been improved. In addition, the larger diameter of the support ball makes it less likely to be buried in dirt such as hand grease, reducing the frequency of maintenance. Focusing on the six hand skeletons and muscles that come into contact during operation, the design considers the depressions and bulges, realizing a new "comfortable feel" that is easy to operate, as if the shape of the palm of the hand is reflected as it is. It has a speed change switch that can switch the pointer movement speed between 1500/750 counts in two stages. It has hardly been used. It was left in the corner of the room, so there are minor scratches, but it is in [good condition]. Thank you for viewing.