Logitech G502 Proteus Core Gaming Mouse - Refurbished Logitech Certified Refurbished - includes a 90 day warranty; includes all documentation Surface tuning calibration: Easily calibrate the sensor to get best tracking performance for your specific mouse pad surface Weight and balance tuning: Adjust the weight, center of balance and placement of weights for personalized feel and performance 11 programmable buttons: Set up one-button triggers to execute any command or macro at lightning speed On-the-fly DPI and dual-mode hyper fast scroll wheel:Quickly switch through up to 5 DPI settings (200-12,000) or temporarily downshift DPI for sniping. Get click-to-click precision for gaming and blazing scrolling speeds for the web