Technical Specifications    Built-in slideshow buttons    50-foot effective range with 2.4 GHz wireless technology    Red laser pointer with LED indicator    Plug-and-play、 no software required    Storable receiver and carrying case    Battery-power indicator    On/Off switchSystem Requirements    Windows-based compute    Windows? XP or Windows Vista?、 Windows? 7 & Windows 8 & Windows 8.1    USB portComplete Package Contents    Wireless Presenter R400(battery not included)    Wireless USB receiver    Manuals