2-1/2" EXTENDED DUST PORT By Peachtree Woodworking - PW452 The 2-1/2" Extended Dust port directly accepts a standard 2-1/4" Shop-Vac hose end. Attach a standard 2-1/2" dust collection hose around the outside of the extended dust port opening. Outside connection requires a hose clamp for proper connections Hose clamp Sold Separately. The fitting itself attaches to the back of most router fences.