This carefully manufactured Electroplated Diamond Reamer is an excellent product for grinding or sanding Thermal Barrier Coatings that may be in cooling holes for turbine blades and vanes. They come in various size diameters ranging from .42mm - 1.27mm. This is a highly specialized tool that can also be used on tungsten carbide, glass, ceramics, nickel based alloys and more. This is not to be used as a drill.Volume discount pricing is available for this product please email us for more information. Minimum of 50 of the same size diameter are required for this order.