Tool Holders Used to Secure Tools in Computer Numerical Controls Machining Devices and Maintain Accurate Standards of Tooling August 19, 2013September 14, 2013 Delicious Bookmark Business Tool Holders Used to Secure Tools in Computer Numerical Controls Machining Devices and Maintain Accurate Standards of Tooling Links like this. Good references here. Keywords: Tool holder, Tool holders, Tool holder, Tool presetter, Tool holders, Tool presetters.