AC Infinity Refillable Carbon Filter Kit, with Charcoal Refill, 4-InchDescription Reusable Carbon Filter: This patented design eliminates the need for replacing entire filters. The package includes over one refill, matching the filtration capacity of two standard 4" carbon filters, thereby offering a cost effective solution. The removable twist off flanges allow for easy, tool free refilling using the included funnel and scoop. Efficient Odor Blocking Capability: The expanded chamber is lab tested to block odors as