The Logitech T-BC21 USB Wired Optical Trackman Red Marble Mouse Trackball is a comfortable and ergonomic trackball mouse designed for precise pointing. With its sleek gray color and thumb button for easy scrolling, this Logitech Trackman Marble model offers reliable performance with optical tracking technology. The wired USB connectivity ensures a stable connection, while the 4 buttons provide accurate control for a smooth user experience. Ideal for those looking for a unique and effective pointing device for their computer setup.