3M Cubitron 3 Depressed Center Grinding Wheel T27 90008

I've got a box of 3M Cubitron 3 depressed center grinding wheels. These are the 7-inch T27 type, 1/4 inch thick with a 7/8 inch arbor. They're 36+ grit and rated for up to 8,500 RPM. The box is open but the wheels are unused. Made in Austria.