Carchalk Inc. 10107 Glass Chalk Sponge Marker

This is perfect for when you want to write a message to people if you get stuck on the side of the road a need a hand.

We used this to write on our car windows in order to sell our car. It rained for only a little bit and paint flowed down the sides of the car doors, making a huge unattractive mess. When we sold the car, we couldn't get the paint off. We used water, soap and water, and windex. I threw away the product.