From the back of the box:
Welcome to Dungeon Lairs - a fantasy roleplaying game aid from the people who brought you Dungeon Floor Plans!
Our artisans have laboured mightily to bring you this new set of complete monster lairs for your dungeon adventures. Inside this box are no less than 15 ready-to-use monster lairs for use in your adventures, with lengths of corridor to link them together. Simply cut the card sheets into individual lairs and you are ready to go!
Even though this was published for WRFP and had WFRP stats for some monsters, it can easily be used for any other fantasy RPG.