*** BIG COMBO Lot of 90 Piecies Tough Diamond Burs Burrs Rotary Tool Bits Rock Grinding Gem Stone 3 Different Grit Levels 40 / 80 /240 Fits for Dremel 40, 80, 240 Grits with 1/8" Shank Dremel Type Tools Approximately 2 inches in length with a variety of head shapes for most application Works great on all natural materials, ceramics, tile, glass, bone & wood Comes in a plastic case for easy storage 90 Pieces