Air Sox are attached to centrifugal, inline fans and are generally used for two purposes in an indoor gardening application. Use Air Sox for filtering air being brought into a grow room. It is important to remove as much dust, insects and fungi as possible. The Air Sox material has been designed to catch as much of these contaminates as possible with minimal restriction of the fan. The second purpose of the Air Sox is air distribution. Typically indoor gardens would have an intake on one side of the room with an exhaust on the other. One problem with this design is that you will potentially have large temperature variances from one side of the room to the other. The Air Sox allows for more even distribution of the air across the entire garden area creating more consistent and manageable temperatures. It will keep cold intake air from blowing on your plants.