Wynn Environmental handles all kinds of industrial filters and generally sells to industry but has a reputation for taking care of woodworkers. They also sell reasonably-priced conversion kits for many DC's. Bill Pentz recommends them and I've ordered from them. I received prompt service (some 6" and 4" DC hose and clamps) and they even repacked everything inside the condensed 6" hose box (10' of hose, ~32" box) to minimize my freight. I'll be doing more business with them in the future.