Carbide drill bit for drilling deep hole Tungsten tip with alloy steel shank Passed ... 9001;High quality OEM is ok. Carbide drill bit for drilling deep holeTungsten tip with alloy stell shankDifferent specifications.OEM is ... ;Passed ISO:9001Mainly used for deep hole drilling, well drilling, metal drilling, masonry drilling, wood drilling and PCB drilling,concrete, clinker, masonry, stone, granite etc. ...