Doktor Doom Foggers flush out and eradicate insects on contact. Contact sprays will not kill eggs or nymphs repeated applications are required. One ounce treats 1000 cubic feet of unobstucted space. [ cubic feet = Length x Width x Height (L x W x H) ] The benefits of using Total Release Fogger is that they are made with natural Pyrethrins which biologically breaks down in a couple of hours after exposure: to light; air flow; and humidity, providing fast re-entry times to fumigated areas. Pyrethrins are a naturally occuring insecticide derived from the Chrysanthemum Flower. For eradicating infestation on plants, Doktor Doom Foggers should be used in conjuction with Doktor Doom Spidermite Knockout. Fragrance free.