Johnsons 4fleas Room Fogger Twin Pack (with I.G.R.) contains permethrin and s-methoprene. Johnsons 4fleas Room Fogger Twin Pack. Kills fleas and other insects e.g. ants, cockroaches, earwigs etc. Prevents hatching eggs developing into fleas. Protects carpets, soft furnishings and pet bedding for up to 7 months. Johnsons 4fleas Room Fogger Twin Pack is a complete room treatment, simply place in room, press and leave.