Norton 4-1/2 x 1/8 x 7/8 Ty-27 Gemini Grinding Wheel 25pk - N662528435914 1 2" x 1 8" x 7 8" Type 27 Gemini Grinding Wheel N66252843591 Upgraded with a new premium aluminum oxide grain for 15% faster cut rate. High performance bond and wheel hardness are designed for fast cut and up to 60% more life and metal removed per wheel. Good choice for grinding 400 series stainless, and hard grade carbon steel applications, especially multi pass welding for pipefitting, notching and any job that requires a quick turnaround.