From the back of the box:
Welcome to Dungeon Rooms a new concept in fantasy roleplaying game aids!
Our teams of Dwarven architects and Elven interior designers have laboured mightily to bring you this new set, with complete, fully-equipped rooms. No dungeon should be without them! Inside this box are no less than 23 ready-made 'special' rooms for use in your adventures, with lengths of corridor to link them together. Simply cut the card sheets into individual rooms and you are ready to go!
User addition:
Although this was published for WFRP and had WFRP stats for creatures in the rooms, it could easily be used for any fantasy RPG.