Each scent comes in either the automatic spray, a twin-pack of candles and ... eight hours of burn time per ounce of candle. Since the Glade candles are now 4.08-ounces each, you're looking ...

Key to the project is the Glade Automatic Spray Air Freshener. This is a battery-powered device with an aerosol can that is operated by either an electronic timer or a push-button switch.