NOTE: In order to safely and effectively use this accessory kit, you must maintain a 4 inch line between the 4" to 2.5" reducer and the main trunk of your dust collection ductwork. This product is not intended for use on waste that wouldn't otherwise go into your cyclone dust collection system, including but not limited to: liquids, metal debris, hot ash or other smoldering materials. Contact Oneida at 800-732-4065 with any questions.