1, crimped end wire brush with carbon, highly specified wire grades are constructed with internal holding plate to ensure consistency & safety constructed for even balance which provides smooth performance, wire is 100% inspected to meet demanding quality specifications, 1 x 1/4 stem, 0.02 wire gauge, 1/4 stem arbor size, maximum speed is 20,000 RPM, Knotted wire is for heavy material removal, crimped wire provides flexibility for light removal of rust & paint & general cleaning. Wire is 100 percent inspected to meet demanding quality specificationsConstructed with internal holding plate to ensure consistency and safety1 in., crimped end wire brush with carbon, highly specified wire grades are constructed with internal holding plate to ensure consistency and safety constructed for even balance which provides smooth performance, wire is 100% inspected to meet demand