Extends the collet by 60mm. When working with a router table that has a thick material table, typically the cast iron type or homemade tables, a collet extension may be required. Certain jobs require the cutter to be lifted above the surface of the table. If the table is thick, there may not be enough plunge depth on the router to achieve this. This collet extension can be used with all 1/2″ shank routers and will lift the cutter by an additional 60mm. A 19mm and a 22mm spanner are required to tighten the collet. To use 1/4″ shank cutters, you can add a collet sleeve (not included) to reduce the collet to 6.35mm.