E-Blue Mazer II 2500 DPI Wireless Gaming Mouse (EMS601BKAA-NF) Upgraded Design with LED illuminated rubberized Scroll Wheel Ergonomically designed for Right-handed Gamers utilizing 'Air wing' Concept Adjustable DPI (Dots Per Inch) switch 500 / 1200 / 1800 / 2500 Avago 5090 High-performance Optical Gaming Chipset 2.4G Wireless Transmission Technology (Stable signal in 30 ft. radius) High 3000 Frame/second Rate for extremely precise Tracking Level Maximum Acceleration 20G / Anti-delay Polling Rate 250Hz OMRON Micro Switch provides Lifespan of up to 5 Million Button Clicks