Twisted Shot 7 - 3D 7 key FPS/MMO Ergonomic Optical Gaming Mouse, With Adjustable DPI Button, and 5 insert-able Weights. For First Person Shooters and MMO Gamers Innovative 3D 7Key Optical Mouse designed for Pro-Gamers and FPS Experts DPI Switch: So you can adjust the DPI settings in game, 400, 1200, 2000, 2800 EASY-TO-INSTALL: Just plug into your computer and driver will automatically download onto your computer. Ergonomically Design: For longer play sessions with 5 inset-able weights that fit into a groove at the bottom of the mouse, and a soft matte finish that feels comfortable to anyone. System Requirements: IBM, PC, or compatible Systems, Dos 5.0 and later. Win7&8/XP/Vista/Linux/Unix