Evoluent Vertical Mouse 2 For Left Handed VMOUSE2H For left handed use only Fast response - 1200 DPI true optical resolution sensor reduces hand movement and makes this mouse great for games 5 buttons, 4 of which are programmable with 59 selectable functions Vertical scroll - press a button and drag the mouse to scroll with greater precision and control than the scroll wheel Auto click - automatically perform a double click by pausing the pointer