Our Combat Mats are designed for the serious gamer. They roll up for easy storage and have a wet erase surface for smudge-free use. Unlike most other mats you have seen, ours are two-sided, providing both one inch square and one inch hex grid systems. Perfect for every role-playing game scenario, small, medium, or large. You can write on them using WET ERASE MARKERS only. We have found the Staedtler Lumocolor 315 pens work the best NOT AVAILABLE outside the continental US.