... head66 6V shape head66206Features Strong, durable, longer life than electroplated diamond toolGood For1. stone monument, tombstone, and so on... carving ... glass, emerald, glass decoration processing.3. Cutting, clearing bottom, drilling, 2D, 3D carvingMaterial applied for:Glass, ceramics, silicon slice, crystal ... , malmstone and so on... Hard and fragile materials procession. Diamond engraving bit