This is another video from our technician Adam Spano. In this clip, he uses two agitation tools, a reverse air snake followed by the spinning brush. The reverse air snake blows jets of compressed air backward toward the operator. He shoots the tool down the duct, then pulls it back toward him allowing the air jets to tear loose the dust and debris adhered to the inner duct surfaces. You can also see him shoot the tool down smaller branch ducts to either side of the main duct, using it to pull debris from the branches into the main where it can be drawn down to the vacuum hookup at the far end of the duct. Adam then finishes off the cleaning by applying the spinning brush. Click the video image below to see the clip.