Flat Oval Spiral Duct Observe the down below video clip to begin to see the set up of oval duct and fittings. Recognize the reducer being used is undersized on its collar allowing for the oval duct to slip about the collar. They are employing Unistrut with threaded rods as https://round-conduit56777.blogoscience.com/43091922/oval-conduit-fundamentals-explained