Mortein PowerGard Indoor and Outdoor Insect Killer Automatic Diffuser Kit the mortein powergard indoor and outdoor automatic insect killer spray unit with refill is designed to provide continuous protection against various insects, including flies and mosquitoes, both indoors and in sheltered outdoor areas up to 25 square meters. Utilizing 98 percent natural ingredients combined with 1.4 percent synthetic actives, it releases regular bursts of mist to maintain an insect-free environment. Refill can last up to 27 days indoors or 24 hours outdoors on the lowest setting.