The baits are formulated with food that specifically attracts German roaches and other small roaches, plus a powerful insecticide, Fipronil, which starts killing within hours. Like all Combat® products, these baits target the nest to eliminate the source of the problem. Combat Max® baits are easy-to-use, child-resistant, need no activation, and can be used anywhere you see roaches. Simply place them down for up to six months of effective roach control. How Combat Max® Roach Killing Bait Works: 1. Roaches enter the bait station and eat the bait. 2. Roaches take the bait back to the nest. 3. Roaches share the bait, killing other roaches and destroying the nest.