AC Infinity 4" Refillable Carbon Filter Kit with Extra Refill — Reusable Charcoal Air Scrubber for 4" Inline Fan & Ducting (Grow Tent / Grow Room Hydroponics)

AC Infinity’s patented refill system removes the need to replace the entire filter housing by allowing only the media to be changed. The kit ships with a 1+ refill that matches the filtration capacity of two standard 4” carbon filters while costing less. Removable twist-off flanges enable tool-free refilling, and a funnel plus scoop are included to make media replacement quick and clean. The enlarged chamber is lab-tested to block odors as effectively as standard filters, with no compression required. Built with dual-layered steel mesh and a protective coating, the unit resists the high humidity found in grow tents and is designed to last through many grow cycles.