AC Infinity Air Filter Box with High Efficacy Filter, 8-InchDescription Duct Filter Box: Designed to be used with inline fans to circulate fresh air and block dust and odors. The box is built using 1mm thick cold rolled steel and aluminum duct flanges, ensuring a sturdy build that can withstand extreme weather. Low Maintenance Design: Features a hinge sealed door equipped with a slide lock which provides easy access to the inner chamber. The door is lined with a soft neoprene layer that securely holds the