... by cnc engraving machine 2,it is good for engraving 3D finishing Specification: Model Shk(mm)Ced ... shape head66206Features Strong, durable, longer life than electroplated diamond toolGood For1. stone monument, tombstone, and so on... carving work.2 ... applied for:Glass, ceramics, silicon slice, crystal, granite, marble, malmstone and so on... Hard and fragile materials procession. Diamond engraving bit