While it's never easy to remove permanent marker, there are some things you can try. This is a guide about removing permanent marker from plastic.
Here are questions related to Removing Permanent Ink (Sharpie) from Plastic.
How to remove sharpie marker off the back of a TV?
Sakeitha from TX
By Sara (Guest Post) 08/22/2007
Try aerosol hairspray. Our local "dented and dinged" grocery store marks their prices with sharpies and they have a sign at the registers to use hairspray if you want to remove the price. Worth a try.
How can you remove Sharpie permanent markers stains from plastic headlamp lenses?
By Jeremy from Richmond, VA
By Pixiedust7  09/18/2010
I have had luck removing Sharpie ink with regular isopropyl alcohol from the grocery store or any drugstore chain. It doesn't harm most surfaces, and usually takes all the ink off.
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