|Most commonly the American Cockroach, variously (though often
incorrectly) called wood roaches, water bug roaches, Palmetto bugs.
These aren't your cute little kitchen German roaches. They are large,
can fly, live outside and come inside for food.
Because these roaches live outside, broadcasting these pellets around the foundation (and underneath, if you have one) stops them cold. It's like magic. The label says you can use them indoors for German roaches too, but I don't know anything about that.
NOTE: A change in the law has made the original active ingredient (poison) in this pellets illegal. They still sell them, but with an new poison. However, I had bought a large supply of the original and have not tried the new version. If you try them let me know if they work as well.