Amazon.com: Flexible PVC Rubber Coupling with Stainless Steel Clamps 4 x 2 Inch, Black : Industrial & Scientific
Amazon.com: 4 inch to 2-1/2 inch Reducer with 4 inch Flexible Cuff Rubber Coupler Fitting and Stainless Steel Hose Clamps with Turn Key Thumb Screw to Easily Tighten and Loosen • Designed
The Plumber's Choice 2 in. x 1-1/4 in. PVC Flexible Reducing Coupling with Stainless Steel Clamps E03842X114 - The Home Depot
HPS High Temp 2" > 3.25" ID x 3" Long 4-ply Reinforced Silicone Reducer Coupler Hose Black (51mm > 83mm ID x 76mm Length) - Walmart.com