Combination of patented Norton SG ceramic and zirconia alumina grain delivers highest productivity Offers up to 10 times the performance of aluminum oxide wheels, 50% to 200% better cut rate than competitive zirconia wheels 1/4 inch thick wheel designed for tough offhand stock removal applications Aggressive, yet well-balanced wheel is easy on the operator and equipment Very high productivity and low total cost for 400 series stainless steel, and cast and gray iron applications Remove stock from 400 series stainless and carbon steels with this Norton NorZon Plus SGZ CA/ZA Type 27 grinding wheel. A well-balanced design enables the wheel to cut aggressively without causing excess wear to your grinding machine. Measuring 1/4 inch thick, the wheel features an abrasive that combines zirconia alumina and Norton SG ceramic grain for performance up to 10 times better than aluminum oxide wheels. Additionally, the wheel produces a cut rate up to 200 percent better than competitive zirconia wheels to boost work efficiency. Package of 25.