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
Kensington Orbit Wireless Trackball with Scroll Ring, Professional Computer Mouse with Bluetooth, (2.4GHz Wireless), Optical Tracking & AES Encryption Security, Left or Right Handed - Black (K70992WW) : Amazon.co.uk: Computers & Accessories
Kensington Orbit Optical Trackball Silver/Grey 64327EU | Printer Base