INFINITER LR-8G 4-in-1 Function: Wireless Presenter with Wireless Mouse/Media Player Control/Smart Drawing Pen functionPowered by 2 AAA Batteries - Included! Easy to use multi-function design for laser pointer, presenter, wireless mouse and Media Player control functions. Output power: Class IIIa, output power is less than 5mW, eye safe laser product. Unique and Practical hot key functions include: page down, page up, play/ESC, and screen blank/back with Power Point Pen function. Sure to assist you in making a professional presentation. Wireless remote control distance up to 32 yards (open space) for freedom to move around the room. Plug-and-play 2.4 GHz wireless USB receiver device with no additional software downloads & driver installation required. Built-in docking bay stores receiver for easy pack up and portability. Works flawlessly on Windows. OS supported for Windows 10, Windows 8, Windows 7, Vista, XP, Android 4.2 or later models. (Notice: This device can't work on OS Mac 10.0 or later, because Mac OS does not support many functions since 2016). Use two AAA batteries (included) for 4 hours operation time. Designed & made in Taiwan with the utmost quality. Pen Function: Draw Lines to highlight the key areas. The pen function is based on the drawing function which is built-in in the Microsoft PowerPoint software. Since Microsoft makes this function complicated when you try to activate or stop it, we would like to suggest that you should practice this function before you are making formal presentation.