... .min order 1pcs 3.a large stock 4.with good tungsten carbide insert 1.Medium soft with low compressive strength and ... gypsolyte, soft limestone, sandstone and dolomite with stringers,etc. 1. Tungsten carbide insert tooth, sealed and gage protection journal bearing,hardfaced ... for water well, oil field, underground, construction, geothermal well,etc hot sell pdc bits ,tricone bits,drag bits