Remote Control-Laser pointer&Sllde Changer Instructions for use: 1.Plug the receiver into the USB port on your PC. 2.To change slides up or down-point the laser controller at the receiver and use the black arrow keys effective operating distance is up to 15m.3.The middle button is a conventional laser pointer.4.The sllde changer is compatlble with:windows 98 SE/2000/ME/XP Linux and Mac OS. 5.Lt supports powerpoint,Excel,Word.Acrobat Reader etc. Caution: Please do not point the laser in the eyes