Swivel Ball Joint connects Spiral Pipe or Flexhose to allow the rotation of a dust or fume hood. Ideal for CNC Router & other machines with traversing heads. Constructed of 20 gauge galvanized steel (Pipe & Hose NOT included).Swivel Ball Joints with TWO proper installation collars - one collar to fit ductwork and a second EXTENDED COLLAR to connect to flexhose allowing proper and free rotation.Click here for Tech Data on Ball Joints