... .8, 6, 7, 11, 12 3.Water Hole: 2 Taper 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 ... bits, thread button bits, retrac button bits, extension rods, shank adapter, coupling sleeve, etc.All the products adopt the best alloy ...