FightEver Wired vertical mouse Superior Ergonomic Design Optical Gaming mice 5 Buttons optical usb health mouse for Alleviate Wrist Fatigue Vertical Mouse Mice 1.Ergonomically designed to reduce strain. 2.Prevention of mouse hand. Five Button,Full Function Mouse. 3.premium-level quality and confort for the price of a conventional mouse. 4.You pick the hand position that best suits you.Plug and play,compatible with Mac and PC. 5.Button: 4 buttons in default / 1 scroll wheel (middle button).