Kaufhof KWY192 4 Inch x 2-1/4 Inch (Shop VAC) Reducer For Wood Shop Dust Collection Dimensions: Height 6-1/2 inch x Depth 4-1/8 inch 4-Inch and 2-1/4-inch Outside Diameter 4-Inch end connects to standard 4-inch dust collection hose 2-1/4-Inch end connects directly to shop vacuum hose Lightweight and portable; made from tough and durable plastic