... (3) Build-in USB Flash (4) PPT Black Screen 2.4GHz Black Screen Green Light Wireless Presenter 1.Product compositionTransmitter 1 Receiver ... button, laser lights; not by the laser light off b.Page Up: support PPT, WORD, EXCEL, Internet Browser, Picture Browser ... , etc c.Page Down: support PPT, WORD, EXCEL, Internet Browser, Picture Browser, ...