USA made KnKut left hand screw machine (stubby) length drill bits and square extractors set is ideal for removal of broken studs and bolts in tight areas. Featuring a 135° split point and 3 flats on the shanks, these left hand drill bits often remove the bolt or stud without the need for an extractor. If the extractor is needed, our square style screw extractor will not chew up or expand the object being removed.