... :300-1250mm 2.Carbon layer: 35mm,50mm 3.High effective 4"-12.5" Hydroponics Activated Carbon Ventilation Filter *Carbon layer thickness: 35mm, 50mm ... : Inline ventilation fan, Grow tent, Carbon filter, Light reflector, Electronic Ballast, Heavy duty hanger, Flexible duct... Rope Ratchet Filter Hanger 4"-12.5" Hydroponics Activated ...