Kensington Expert Wireless Trackball Mouse (K72359WW) Black, 3.5" x 6.1" x 8" & Orbit Wireless Trackball Mouse with Touch Scroll Ring (K72352US),Black

• Product 1: Large 55mm ball design and Diamond Eye optical tracking for precise cursor control. Patented scroll ring lets you scan up and down pages with ease Product 1: Detachable, ergonomic wrist rest supports hand and wrist for improved comfort. Ambidextrous design Product 1: Customizable 4-button design, scroll speed and cursor speed via KensingtonWorks software Product 1: Connects wirelessly via built-in Bluetooth 4. 0LE or with the USB dongle using 2. 4Ghz wireless. Auto-sleep helps conserve battery life Product 2: Optical tracking for superior cursor control Product 2: Unique touch scrolling — simply slide your finger around the outer ring of the trackball for effortless scrolling through web pages and long documents Product 2: Free downloadable KensingtonWorks software provides button customization Product 2: Ambidextrous design