The Logitech TrackMan Marble T-BC21 USB Trackball Mouse is a wired optical trackball mouse with a red ball for easy navigation. It features a maximum DPI of 300 and four buttons, including a thumb button for added convenience. The mouse is designed by Logitech, a trusted brand known for quality and performance in computer peripherals. With its unique trackball design and USB connectivity, this trackball mouse offers a comfortable and efficient way to navigate on your computer or tablet.