4 InLine Fan Carbon Filter & Duct Kit Hydroponic Grow Room Ventilation Clip Fan. The item "4 InLine Fan Carbon Filter & Duct Kit Hydroponic Grow Room Ventilation Clip Fan" is in sale since Tuesday, October 1, 2013. This item is in the category "Garden & Patio\Hydroponics\Fans, Filters & Environmental Control\Air Ventilation & Extraction". The seller is "fans4less_limited" and is located in Earlswood/Solihull. This item can be shipped worldwide.