Designed to perform, the open-air structure creates maximum surface area and space for air flow to provide effective fragrance release. Dry fragrance technology doesn't contain any propellants or acetone so they are cleaner and there's no sticky residue. Part of Fresh Product's closed-loop recycling program and are 100% recyclable. Releases fragrance for 30 days without fragrance overload. The refill is solid that has been infused with natural fragrance oils so the air you breathe is chemical-free and there's no messy gels or liquids. Made specifically for use in the Eco-Air dispenser.