The Wokin 10 Pack 4.5" Grinding Wheels for Metal is a set of high-quality grinding wheels suitable for use with an angle grinder. With a diameter of 4.5 inches and a thickness of 1/4 inch, these black wheels are designed for cutting and grinding tasks. These wheels are lightweight at 4 - 1 / 2" x 1 / 4" x 7 / 8" and offer a maximum speed of 13,300 RPM for efficient and precise grinding. The Wokin brand ensures reliability and top-notch performance, making these grinding wheels a must-have for any workshop or home improvement project.