Set your router bit to the precise height every time! Simply bring the router bit up through the table and align the jig with the cutting edge of the bit.. This system is ideal for making accurate rail-and-stile construction, lock miter joints and more. All jigs are manufactured for 3/4" stock. They are made of durable HDPE and measure 2" x 3-7/8" x 3/4". (Jigs designed for rail-and-stile have the rail cut on one side and the stile cut on the opposing side.)