The mere sight of these tiles is enough to trigger a clausrophobia attack!
If you have need for lots of narrow twisting corridors, bestrewn with pits, crossed by suberranean rivers and with an assortment of traps magical and mechanical, this is well worth a look.
The presentation is nice and crisp, with a good geomorphic design. The tiles are ink-hungry but it's well worth it for the results - a dramatic and quite terrifying display on your tabletop.
All you need to do is decide on a layout (or indeed randomise the tiles, the geomorphic design facilitates this) and pick out whatever monsters, traps and other hazards you want to use... then find a way to get those suckers, er, sorry, player characters to go there...
If a classic 'dungeon crawl' features in your plans, this is a good resource for presenting it vividly to your players.