This dust collection adapter lets you attach commonly available 1-1/4'' O.D. shop vacuum wands, including those found on most Shop-Vac models, to standard 2-1/4'' I.D. dust collection ports. The narrow end fits onto 1-1/4'' diameter shop vacuum wands and fittings, while the wider end fits into the 2-1/4'' I.D. dust ports found on router table fences (including Rockler and Bench Dog), dovetail jig dust collectors and more. Durable hard-plastic construction. Friction-fit; no clamps necessary.