BluApple Ethylene Gas Absorption Starter SetThe Bluapple starter includes 2 refrigerator safe bluapple ethlylene gas absorbers, for produce preservation. Save hundreds each year by keeping fruits & vegetables fresh longer. Each Blue Apple lasts for 3 months. Refills available. BluApple Ethylene Gas Absorption Starter Set 2 Blue Apples for Produce Preservation Using the BluApple ethylene gas absorption system, you can extend the useful storage life of your produce up to three times longer. USDA