The Top-Trak is a self-aligning 610 mm L-shaped profile for easy installation to a shop-made fence. Just drill 3 mm holes through the back of the extrusion and secure with the included mounting screws. As soon as it is installed, the Top-Track can hold a Kreg Production Stop as well as a Swing Stop™. Combined with Kreg self-adhesive measuning tapes you can easily upgrade your workbenche to a workstation with flexible stops and accurate measure.