Built for left-handed users, as well as to provide relief from Carpal Tunnel syndrome, the iMouse E90 Wireless Left-Handed Vertical Ergonomic Mouse from Adesso features a vertical orientation and a contoured shape that helps provide a comfortable user experience. It lets users keep their hand in a "handshake position," which is a neutral position of the forearm and helps prevent forearm twisting. Built with 2.4 GHz wireless connectivity, this mouse has six buttons, which include forward and back buttons, left and right mouse click buttons, a middle button, a scroll wheel, and a dpi button that lets you adjust between 800, 1200, and 1600 dpi. Powered by two included AAA batteries that last for up to 6 months, this mouse works on most glass, wood, marble, and leather surfaces without a mouse pad and has an operation range of up to 30'. It interfaces with your host Windows 10, 8, 7, Vista, XP, and 2000 system using an included USB Type-A nano receiver.