PureAir PK-2 Produce Keeper PlusKeep fruits and vegetables fresher longer with the PureAir PK 2 Produce Keeper Plus. Now you can help preserve the taste, color, and freshness of fruits and vegetables with this advanced filter. It uses antioxidant technology to capture and neutralize ethylene gas, the natural gas that causes produce to ripen quicker. The PureAir PK 2 Produce Keeper Plus also has a carbon layer that clears the air and absorbs undesirable odors to maintain freshness