For professional installation of handles and knobs. It is the highest quality modular cabinet hardware jig on the market. Designed for the installation of a wide range of handles & knobs. Locating holes on door and drawer fronts has never been easier. An invaluable tool for the cabinet installer. Simply slide guides and stop along Metric rulers, tighten thumb screws and drill. It is the core unit of the complete drilling system. lightweight aluminum with case hardened steel bushings. Package includes two straightedges，two sliding guides，a sliding end stop and a top stop. And an electric drill is needed. First, you can assembly as shown,and then use the imperial/metric ruler to set the hardware spacing. Next, please make location and start drill at the desired location. At last,hold-in-place and repeat the operation and drill the other end.