Johnsons 4fleas room fogger kills fleas and contains IGR (Insect Growth Regulator) which also prevents hatching eggs from developing into fleas. Use to protect carpets, soft furnishings and pet bedding from fleas and other insects (e.g. ants, cockroaches, earwigs etc.) for up to seven months. Johnsons 4fleas room fogger is easy to use, simply place in a room, press the activation button and leave. A single 4fleas room fogger will treat an area of up to 35 square metres.