This is the path name of the DLL which provides tool and material information to SURFCAM. The default tool library is ToolLib.DLL and is installed to the main SURFCAM directory. This allows the advanced user to replace the tool library with one of their own that provides the same services.
If this box is left blank, the Tool and Material libraries will not be available to you. A different Tool Information tab will be displayed in which you will have to enter all of the tool features yourself.