Assistive Technology Loan Library item === 3M's Ergonomic Mouse is an optical mouse that looks like a joystick yet it functions like a mouse. You rest the back of your hand at the base of the mouse and your thumb on the switch at the top of the stick for easy right and left clicks. A third button is located on the handle and can be used as an auto scroll button in Windows or as a standard third programmable button. Ergonomic Mouse requires only slight flexing of your wrist and slight pronation of your hand, which results in low pressure in the carpal tunnel. The Ergonomic Mouse is available in two sizes: Standard, palm widths less than 3.5 and Large, palm widths 3.5 or greater. This mouse is standard sized. Website: various websites.