Kensington Trackball Mouse - Wired Ergonomic Orbit, For PC, Mac and Windows with Scroll ring, Ambidextrous design and Optical tracking ideal for Home Office - White (K72500WW),40 mm Ball : Amazon.co.uk: Computers
Kensington Orbit Trackball with Scroll Ring review: Kensington Orbit Trackball with Scroll Ring - CNET
Kensington Orbit with Scroll Ring Wireless Trackball - Black
Kensington Orbit Mouse - Wireless Mobile & Compact Ergonomic TrackBall Mouse for PC, Mac and Windows with Touch Scrolling, Ambidextrous Design and Optical Tracking - Red (K72352EU) : Amazon.co.uk: Computers & Accessories
Kensington Orbit Mouse - Wired Ergonomic TrackBall Mouse for PC, Mac and Windows with Scroll Ring, Ambidextrous Design and Optical Tracking - Blue (K72337EU): Amazon.co.uk: Computers & Accessories