Give your router bits an additional 2-1/4-inch when you extend them through the router table top with our router collet extension. Eliminate the dangerous temptation of withdrawing the shank from the collet in order to raise the bit and to provide the full depth of cut. The router collet extension makes it possible to use all diameters of 1/2-inch and 1/4-inch shank bits safely. Place the router collet extension shank in the 1/2-inch router collet and the router bit shank in the extension collet and tighten both. Instructions included. Use with 1/2-inch collet routers only.