This set of two Carborundum grinding wheels is perfect for your metalworking needs. With a diameter of 3 inches and a hole diameter of 3.8 inches, they are designed for a  maximum RPM and efficient performance. The wheels are made of high-quality carbide abrasive material, ensuring durability and longevity. The brand is Carborundum, T.M. Niagara Falls, NY, and the construction type is Max RPM 8276. The wheels are made in the United States and come with a width of 3/8 inches. They are suitable for use with angle and die grinder wheels, and are ideal for those in the CNC, metalworking, and manufacturing industries.