Karnotech 2.4Ghz Wireless Mouse with USB Receiver 1200 DPI Portable Mice with Mute & Hidden Windows & Lock Screen Keys (VMW-172 Black) Adopting 2.4 GHz wireless technology to provide a reliable connection without delay or frame skipping. Powered by one AA battery (not included). Ergonomic shape and textured rubber grips keep your hand comfortable even after long hours of working. For PC or laptop compatible with Windows, Mac and Linux. Works well on any surface without mouse pad, such as couch or table. "Lock Screen Key" on the left side allows you to lock the screen anytime with simple one-click. "Hidden key" on the top to minimize open windows to the desktop and mute the sound.