Dura-Grit are powerful, long lasting shaping tools that finish as they cut! They are unique, strong, carbide coated steel shapes, mounted on strong, 3mm diameter heavy duty mandrels. Made with tungsten-carbide grit in sandpaper grades, braze welded to steel, Dura-Grit tools are extremely strong and aggressive. The tungsten-carbide grit won't tear loose and remains sharp over a very long period of use. Exhaustive testings repeatedly show Dura-Grit tools outlasting sandpaper hundreds of times. These tools need little cleaning, however, residue can be removed by running the tip into the bristles of a wire/stainless brush or into uncured rubber. Any of the burr tips can be unscrewed from the mandrel and fibre washer and soaked in solvent (Acetone), or burned clean with a propane torch without damage. Cleaning the burr will restore the cutting surface to virtually new and extend the working life of the tool.