Refill is easy to use in Febreze Set and Refresh, Febreze Stick and Refresh, and Febreze smallSPACES dispensers (all sold separately) to keep the freshness going strong. Simply place the scented oil refill cartridge in the dispenser to activate the freshness of Febreze. When you hear the click, you'll know the refill is activated. The dispenser is designed to activate the cartridge without the need to peel or open anything. Scented oils wick the entire membrane, which allows the oils to continually release from the cartridge to freshen the air.