Darkfield™ laser tracking gives you flawless control on virtually any surface, including glass and high-gloss surfaces. This wireless travel mouse performs anywhere you need it to—glass tables in your hotel room, shiny laminate tops, train and airplane tray tables, and even your jeans. Unlike traditional laser and optical mice which use irregularities on the surface to track mouse movements, Darkfield technology uses the smallest possible detail to create a micro-road map of the surface. In tests, the mouse performed best on glass with a minimum thickness of 4mm.