Evoluent VM2-LSB VerticalMouse 2 Optical Left Hand - Silver/Black Reduces Hand Movements: 1200 dpi true optical resolution sensor moves the pointer quickly to reduce hand movements Easy Clicking: The button force is light for easy clicking, but still firm enough to avoid accidental actuation Programmable Buttons: 5 buttons each programmable with different functions in different applications Speed toggle: Cycle among up to 3 pointer speed settings by keyboard shortcut or mouse button Auto click: Automatically perform a single or double click by pausing the pointer