Eight piece Stud/Bolt Extractor. Internal Screw type for removing right hand threaded Studs, Bolts large screws and threaded pipe. This type of Extractor is commonly used on Bolts/Studs that have snapped off flush preventing the use of external Extractors. Simply drill the bolt/stud to the correct size for the corresponding extractor then screw in the correct size Extractor in an anti-clockwise direction. PLEASE NOTE: These Extractors are designed to be used on FREE (NOT Seized) Studs.