Kensington Orbit Optical USB Mouse - 64327EU | CCL
Kensington Orbit TrackBall - Wired Ergonomic TrackBall Mouse for PC, Mac and Windows with Ambidextrous Design, Optical Tracking & 40 mm Ball – Space Grey (64327EU), Silver : Amazon.co.uk: Computers & Accessories
RT07900 64327EU Kensington Trackball Orbit Optical USB | eBay