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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 Expert Mouse - Wireless Ergonomic TrackBall Mouse for PC, Mac and Windows with Ambidextrous Design, Optical Tracking, Scroll Ring & 55 mm Ball – Red (K72359WW) : Amazon.co.uk: Computers & Accessories