Raid Max Perimeter Protection keeps German cockroaches out. This insecticide keeps killing German cockroaches for up to 18 months on non-porous surfaces and can be used both indoors and outdoors. Kills a wide variety of insects such as Ants, Fleas, Flies, Gnats, Roaches, Ticks, Silverfish, Crickets, Spiders, Mosquitoes, Centipedes, Firebrats, Small Flying Moths, Stink Bugs, Sowbugs, Ground Beetles, and Boxelder Bugs.