Dust Collector 4" to 2.5" Duct Reducer ABS Plastic 4" OD & 2.5" OD Opening 73448
These reducers allow fitting of a 2.5" dust collection hose to a 4" hose. Overall length is 3.5". Has a flange to allow easy assemble/disassemble. One end has 2.5" OD and 2.3" ID opening and the other has 3.940"OD and 3.700" ID opening.