ball nose engraving bit material:solid tungsten carbide engraving materials:wood,plastic,PCB board,aluminum ball nose engraving bitmaterial:solid tungsten carbideengraving materials:wood,plastic,PCB board,aluminumSIZE: SHANK:FROM 3MM TO 6MM OVERALL LENGTH FROM 42MM TO 60MM DRILLING LENGTH:20MM TO 32MM Ball Nose Engraving Bit