4-1/2x1/4x5/8 metal. For use on angle grinders. Industrial grade, aluminum oxide grinding wheel for heavy-duty cutting, grinding, and material removal applications. Double reinforced for increased life and faster cuts. Ideal for low angle and vertical grinding. A24R grit. Bulk. 4-1/2" x 1/4" with 5/8-11" arbor, 12,000 RPM