Couplings slip inside the ends of two round ducts being joined alongside one another and after that sheet steel screws are fixed to hold it in place. Couplings may very well be required at a certain measurement like connections 18” and bigger. The shaded region from the graphic below may https://juliusewncq.ssnblog.com/35635672/helping-the-others-realize-the-advantages-of-round-conduit