Check the listing for details. POWERTEC Dust Collection Threaded Quick Coupler Adapter, 4 x 2-1/2" (70171). Condition: New. Listed at 13.18 USD. Allows quick and convenient connection and disconnectionFits 4 in. tapered ports and 2-1/2 in. threaded hosesDesigned for durability and made to withstand the wear and tear The POWERTEC 4 in. x 2-1/2 in. Threaded Quick Coupler quickly connects a machine's 4 in. dust collection port to a 2-1/2 in. dust collection hose. The 4 in. I.D. end is designed to press onto a 4 in. Dia tapered port. The opposite 2-1/2 in. end simply threads into a 2-1/2 in. dust collection port. No hose clamps are required. 4 in. Nominal end measures 4-13/64 in. tapered O.D., 3-31/32 in. tapered I.D.4 in. I.D. end presses onto any 4 in. Dia tapered dust collection port2-1/2 in. end threads into a 2-1/2 in. dust collection hoseNo hose clamps are requiredTotal length: 5 in.Threaded 2-1/2 in. end length: 2-3/4 in.; 4 in. end length: 2-1/4 in.Provides a quick, easy and tight-fitting connectionEnsure that your dust collection operates at peak efficiency and performance