Kill for 24 hours. Kills mosquitoes that may carry West Nile and Zika. Bengal Yard and Patio Mosquito Fogger is an outdoor product for use in backyards, patios, decks, porches and other areas where listed flying insect are a problem. When sprayed on surfaces outdoors, Bengal Yard and Patio Mosquito Fogger residually kills listed flying insects that land on treated surfaces for 24 hours. Guaranteed to work or your money back. Guarantee: If you are not completely satisfied with this Bengal Product, call 225-753-1313 weekdays 8:30 am - 4:00 pm Central Time. www.bengal.com.