... in USB Flash (4) PPT Black Screen 2.4GHz Black Screen Green Light Wireless Presenter 1.Product compositionTransmitter ... button, laser lights; not by the laser light off b.Page Up: support PPT, WORD, ... In the PPT full screen mode, you can achieve a black screen, the screen goes black e.Piece ... 40*33*22cm weight:8kg 5.Product Colorstock:black,red,blue 6.ApplicationsTeaching, lectures, exploration, and ...