The Dremel 84922 is a silicon carbide grinding stone for use with 4000-6/50 rotary tool, 4000-3/34 rotary tool, 4000-2/30 rotary tool, 300-2/28 rotary tool, 200-1/21 rotary tool, 100-n/7 rotary tool, 8200-2/28 rotary tool, 8200-1/28 rotary tool, 8000-03 rotary tool, 1100-n/25 rotary tool, 750-02 rotary tool, 7700-1/15 rotary tool, 709-01 rotary ...