This is a 14-inch diameter electroplated diamond grinding disc with the face completely covered with diamonds.
It has 150 square inches of grinding surface.  There are two parts, the 14" diamond disc and the 12" magnetic backed bat, both pieces are included.  Medium/coarse, #100 grit.

Attaches directly to a potter's wheel with standard bat pins, 10" on center, with the included 12" magnetic backed bat.

Ready to attach to your wheel and work, no assembly.

 
Works for high fired porcelain, stoneware or bisque.  Each disc is machined flat before electroplating for an even, very effective operation, and evenly distributed consistent grit particle size. 

Use with water.