MARVO M-316 Ergonomic Wired Mouse,7 Soothing LED Colors,6 Buttons,4 DPI gaming mouse Surface tuning calibration: Easily calibrate the optical 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 7 programmable buttons: Set up one-button triggers to execute any command or macro at lightning speed Supports Windows 10, 8, 7, Vista, XP or later operating system. Package contents: Gaming Mouse, tuning weights, and user manual Ergonomic either hand design,Built-in weight iron, offer excellent feeling for playing games