COMBAT® source kill large roach baits are formulated with food that specifically attracts American roaches and other large cockroaches, plus the powerful insecticide, hydramethylnon. This combination gives you complete control by killing the nest, getting rid of the problem at the source, these easy-to-use, child-resistant baits need no activation. Simply place them down and relax while they continuously work to eliminate large roaches day and night.