There are many ways to attach an extract fan or your carbon filter. However if you are serious about having the best you can get for your grow room, then you should not settle for anything less than fast clamps! They ensure the connection is completely sealed in an air tight fashion without any annoying vibrations. They are constructed of a wide metal collar that is lined with a dense layer of foam on the other side. This wraps around the two spigots of your fan and filter (or silencer) and is secured with a bolt that allows the foam to form an immensely strong connection that leaves no gaps for unfiltered air to escape from. It will not pull apart even when things are moving around and by directly connecting the fan to your filters saves space and improves air flow. They really are a no-brainer!