Question Gray stains on monitor hardly washes off

Vilza

Prominent
Mar 3, 2019
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510
Gray stains on my both monitor hardly washes off. i have them for quite some time now and it looks really bad can u tell me were are the from and how to clean them
Stains
 
As long as they are not actually in the screen, I have used the magic eraser to clean several monitors. I had my son years ago draw with marker all over a $500 high end monitor, used the magic erase and it took it right off. One thing you need to watch out for is that it is abrasive so may take off some coating.