The key distinction is whether the tool is designed to be interchangeable — that is, mounted in and removed from a power tool, machine tool, or handtool chuck. Drill bits designed to be chucked into a drill (power-operated or hand-operated) are interchangeable tools and belong under 820750 in heading 8207. A fixed, non-removable boring element that is part of a complete tool assembly would follow the classification of that assembly.

The split follows the material of the working part — the portion that actually contacts and cuts the rock or earth. If the cutting element is made of cermet (a ceramic-metal composite such as tungsten carbide in a cobalt binder), the tool falls under 820713. If the working part is made of any other material, including high-speed steel or diamond, it falls under 820719. Manufacturer material specifications are the primary evidence for this determination.