Here's How it Works: Mint oil overstimulates insects' nervous sytem and/or clogs insects' breathing holes causing asphyxiation and death. Residual effects last up to 4 weeks. Fresh mint scent with no toxic chemical residue. Safe around people, pets and wildlife. Will not stain carpets or floors. Certified poison free by Scientific Certification Systems. Application Recommendations: Shake can upside down for 15 seconds. Spray and soak bugs completely. Spray surfaces where bugs crawl (inside or outside). Repeat application if necessary. Residual effects last up to 4 weeks. May cause irritation if comes in contact with skin or eyes.