spare parts of drilling machne,tapered button bits,button bits,rock drill ... ,taper chisel bits and taper cross bits.1. Bit Type: spare parts of drilling machine2. Diameter : 28mm – 45mm3. Taper: 7 degree, ... , 25mm 5. Bit Body: Short skirt and Long skirt6. Water Hole: 3Compared with tapered chisel bits and tapered cross bits ... 5A3 7A4 6A6)D45b6A6-7227°(6° 11° 12°)45506A6 spare parts of drilling machine