Flat Oval Spiral Duct Look at the beneath online video to see the set up of oval duct and fittings. Observe that the reducer being used is undersized on its collar enabling the oval duct to slide more than the collar. These are utilizing Unistrut with threaded rods as hangers https://round-conduit91123.answerblogs.com/36996167/new-step-by-step-map-for-round-conduit