Flat Oval Spiral Duct Watch the under online video to see the set up of oval duct and fittings. See that the reducer getting used is undersized on its collar allowing the oval duct to slip about the collar. They are employing Unistrut with threaded rods as hangers with the https://zionaqetk.verybigblog.com/35674496/what-does-oval-conduit-mean