Kensington Expert Mouse Wired Trackball, Ambidextrous, Optical, USB Type-A, 400 DPI, Black Kensington Expert Mouse Wired Trackball. Form factor: Ambidextrous. Movement detection technology: Optical, Device interface: USB Type-A, Movement resolution: 400 DPI, Buttons type: Pressed buttons, Buttons quantity: 4, Scroll type: Ring. Product colour: Black https://www.eteknix.com/kensington-professional-trackball-pro-fit-gesture-mouse-review/ It seems we can't go a whole week here at eTeknix without reviewing some revolutionary, feature packed, gaming focused peripherals, but there's a whole other world of hardware out there for the professional market, and that's exactly what we'll be taking... The trackball mouse is designed to be an alternative to the traditional mouse, with the cursor controlled by a large weighted ball. The ball itself is approximately the size of a snooker ball, finished in a sparkly grey effect. Nostalgic memories of fu... Excellent precision and comfort, symetrical design for left and right hand use Not as smooth to navigate as advertised https://www.techadvisor.co.uk/review/mice-tracker-balls/kensington-optical-expert-mouse-review-108108/ The Kensington Optical Expert Mouse trackball mouse is designed to be an alternative to the traditional version, with the cursor controlled by a large weighted ball. The ball itself is approximately the size of a snooker ball, finished in a sparkly ... We wont be replacing our mouse with this trackball version for professional work, but for users seeking an alternative hand position this Kensington Optical Expert Mouse may be just the ticket. It’s also very handy when desk space is restricted. Joh...