IowaDan, Just installed the hose mod. on a 320 flex. Using 3"O.D. non-perforated,corrugated black tile. All materials(2-10ft.tiles,2-end caps,1-conn.,10-conduit hanger straps)run less than $20. Takes about 30 min. to install. Takes longer to shape the conduit hangers to fit around the tile than it does to install. Good luck, Hyper Harvest II