Gale Force Nine?s Official DUNGEONS & DRAGONS Game Mats are high-quality single-sided vinyl surfaces that are ideal battle grids for staging encounters during your adventures! The mats lie flat for ease of play and are sold in a sturdy polycarbonate tube for easy storage and transport. The mats may be marked with WET-ERASE markers to temporarily alter terrain areas or make other notes about battlefield conditions during play. The Game Mats measure 20? x 30? and are marked with a 1? grid. All of GF9's Game Mats are based on artwork provided by Wizards of the Coast.