... : 4.8, 6, 7, 11, 12 3.Water Hole: 2 Chisel Rock Bits We are a manufacturer specializes in producing kinds ... of rock drilling tools includes taper chisel bits, cross bits, button bits, tapered drill rods, integral drill ... :15,19,22,24,25(mm) Drill TypeBit diamater (D)TaperWhter hole(d)mmPart onmminChisel Type Bits301 3/167°222Y130-722321 17 ...