Logitech Wireless Mouse 320, Blue Curves designed for total comfort Crafted for your hand Long battery life Smooth and precise tracking Plug-and-forget Nano receiver Right-handed contoured design: Curved soft rubber side grips for extra comfort 2 year battery life: Go longer between battery changes (Battery life may vary based on user and computing conditions) Logitech Advanced Optical Tracking: Enjoy ultra-precise and responsive cursor control Plug-and-forget Nano receiver: Reliable wireless connection with a small receiver that can stay in your computer's USB port Wide compatibility: Works with Windows 8/7/Vista/XP, Mac OS X 10.5 or later, Chrome and Linux Kernel 2.6 operating systems