Kensington SlimBlade Trackball Mouse (K72327U) & Expert Wireless Trackball Mouse (K72359WW) Black, 3.5" x 6.1" x 8"

• Product 1: Low-profile shape and silver metallic finish deliver ergonomic comfort and beautiful aesthetics Product 1: Requires less arm and wrist movement (for better comfort) and takes up less desk space than a traditional mouse Product 1: Laser tracking delivers precision cursor control Product 1: Ambidextrous design Product 2: 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 2: Detachable, ergonomic wrist rest supports hand and wrist for improved comfort. Ambidextrous design Product 2: Customizable 4-button design, scroll speed and cursor speed via KensingtonWorks software Product 2: Connects wirelessly via built-in Bluetooth 4. 0LE or with the USB dongle using 2. 4Ghz wireless. Auto-sleep helps conserve battery life