Cm Storm Alcor PC Mouse, PC / Mac, Built-in Storage Capability, 2-ways Avago 3090 optical sensor ensures high precision movement On-the-fly DPI adjustments  4 levels and up to 4000 DPI setting Right-handed Ergonomic design provides a firm and comfortable grip. Highest grade Japanese Omron switch guarantees 5 million clicks Multi-color LED illuminated CM Storm logo for distinguishing current DPI level.