Raid Flea Killer Plus Fogger kills fleas and hatching eggs at the source and allows you to treat an entire room with a water based formula. Kills fleas and hatching flea eggs for up to 4 months for continued defense in your home. Do not use this flea bomb in rooms smaller than 5 feet by 5 feet. Extinguish all flames and turn off fans before use. Cover food utensils waxed floors and furniture stereo equipment and other delicate items with newspaper. Fog from this flea killer spray in home lasts for 2 hours. Ventilate for 2 hours after application. The Raid® Defense System uses a combination of products to help you work smarter not harder when fighting bugs in your home. This insecticide is in the form of a fogger that will aerate in the desired space.