Mortein Naturgard Auto Protect Indoor system gives you the control you need to enjoy protection from pests everyday. Mortein Naturegard Auto Protect releases regular bursts of mist to continuously keep your home protected from insects. (Controls flies, mosquitoes, moths, ants and American cockroaches and helps control German cockroaches and fleas.) Now a red flash will indicate that the refill needs changing ensuring continuous protection. The adjustable time settings give you the control to select between three levels of spray frequency, allowing you to adjust the protection to reflect the insect activity in your home. It can also be switched off for those times or days you do not need protection. Over 24 hours the system disperses no more spray than a single 3-4 second spray of regular fly spray.