The Porter-Cable 42188 is a router sub-base. The Porter-Cable sub-base, with its extra large, 2-1/2 inch center hole, allows the use of larger diameter bits than a standard sub base. It is constructed of clear plastic, providing better visibility. The sub-base installs easily, using existing screws from router base.
Extra large center hole, allows use of larger bitsInstalls easily using existing screws in router baseSub-base for Porter-Cable router models (690, 691, 693, 9690 and 693PK)
Router Sub-Base
Supporting routers