The new Logitech MX518 is a Gaming-Grade Optical Mouse that features 1600 dpi resolution with ability to downshift on the fly to as Low as 400 dpi . Any PC gamers will tell you they look to their mouse for a winning edge in a combat game. In the past the choice of mouse setting was always a choice between maximum speed or optimum precision. With the new Logitech MX518, gamers no longer need to choose between the two. The mouse puts quick-shift controls at gamers' fingertips - with one click, gamers can instantly increase and decrease mouse resolution from as high as 1600 dots per inch (dpi) to as low as 400 dpi. And, no software is required.