Pathfinder Flip-Mat: Haunted Dungeons Multi-Pack - Rules of Play says:

Few locales inspire more horror among fantasy gamers than the dungeon, and GameMastery Flip-Mat: Haunted Dungeon provides tons of terror and traps to trouble legions of would-be heroes! With a full dungeon level on each side, this durable accessory can serve as any deadly dungeon in any tabletop fantasy campaign! This portable, affordable map measures 24" x 30" unfolded, and 8" x 10" folded. Its coated surface can handle any dry erase, wet erase, or even permanent marker. Usable by experienced GMs and novices alike, GameMastery Flip-Mats fit perfectly into any Game Master’s arsenal!