Availability: In stock Chessex: Water Soluble Markers (4): _x000D__x000D_ These water-soluble overhead-projection pens work well with the mats. The black, blue, and green colors are the best regarding being removed with water. The red has a tendency of staining much more than the other colors so it is best used for highlighting only._x000D_ Never use dry erase, permanent, or grease-pencil markers. The vinyl is too porous for the lines created from them to be able to be removed. If you have any doubt of the suitability of any particular_x000D_ marker, draw a small line on the border, let sit for awhile, and see how well it can be removed. Better to have a small permanent blemish on the edge of the mat than a permanent map drawn on the entirety of the mat! _x000D_ _x000D_ The four-pack contains one red, blue, green and black marker. _x000D_ _x000D_ CHX03154