Raid Ant & Cockroach Killer Powder has been developed to effectively control cockroaches and ants. The dust particles from the powder formulation are picked up by the insect. On most surfaces, with just 60 seconds of contact, ants and cockroaches will start dying within 30 minutes. The product provides continuous protection and helps guard against re-infestations for up to 12 weeks. It can be used in the home, cellars and dry outdoor areas adjacent to buildings, e.g. paths, patios. Apply along runs, trails, cracks and crevices on doorsteps, window frames, and air bricks. Leave the product undisturbed and dry for maximum effect. Re-apply if necessary after 12 weeks.