7degree 40mm High Efficient Quarry Tapered Carbide Morse Screw Drill Bit  Product Description40mm tapered carbide drill bit set :1.Product Name:tungsten carbide taper carbide drill bit set .TypesTapered chisel bits, Tapered cross bits, Tapered button bits2.Application:Tapered drill bits are used in granite and marble quarry, gold mine, railway, tunnel, etc. for drilling3.Feature:Tapered drill bits connect tapered drill steel of rock drill for drilling holes4.Material:High quality carbide and high quality steel5.MOQ:No requirement for testing and trial order  we can design a...