Feature:* 100% brand new* Ergonomically designed to reduce strain* Prevention of mouse hand* User convenience with wow-pen's signature， pen-grip comfort.* Five button， full function mouse* You pick the hand position that best suits you. Plug and play， compatible with Mac and PC.* Specifications :-- Interface: USB (Cable 1.5m/5ft)-- Resolution: 800dpi-- Button: 4 buttons in default / 1 scroll wheel (middle button)-- Operation System required : Windows 98/Me/2000/XP/Vista/Win 7-- Dimension: 102(W) X 85(D) X 72mm(H)-- Weight: 200g (include USB cable)