Tired of putting up with the wet sticky residue of metered aerosols! Then, put up ourfresh[TM] 2.0. Dry fragrance technology, liquid free, leaves no sticky residue. Eco friendly refills are 100% recyclable and are VOC compliant. Contains the odor neutralizer moc3[TM]. Superior 30-day performance. Smart chip technology runs the fan intermittently, turning longer as the 30 days progress (the fan does NOT run continuously). Easy to refill. Hang approximately 6' high in the center of the space; no need for a ladder. Light sensitive, fan runs at regular program setting when there is light (natural or artificial) and runs at half program when dark. Requires one C alkaline battery. Removing the battery starts the program over at day one. Green light blinks every 7 seconds when fan is running, Red light blinks when battery is low or on day 30.