TERRO Drain Insect Killer is a powerful solution designed with a dry foam formulation that contains three Insect Growth Regulators (IGRs). Unlike liquid drain products, this unique formulation reduces the chances of missed areas and provides full-contact, 360-degree coverage, making it highly effective in tackling and preventing insect infestations. The IGRs in TERRO Drain Insect Killer break the life cycle of drain flies, fruit flies, house flies, and roaches. Shop now: https://amzn.to/401pxO2 To effectively use TERRO Drain Insect Killer, apply the foam into and around the downspout and catch basin to cover the entire area. When treating a double-basin sink, apply it in both drains. It's important to thoroughly coat these areas, as fly larvae tend to develop in the scum buildup on the sides of drainpipes. This product can be used on all types of pipes.