Left Hand Stub Drill Bit for removal of right hand threaded broken bolts or studs without tightening. Use with screw extractors for those hard to remove bolts or studs. Industrial, polished finished with 135 degree split point. Made from premium cobalt steel. Stubby mechanics length drill bit for additional strength. 5 Piece Set includes 1/8-Inch, 3/16-Inch, 1/4-Inch, 5/16-Inch, and 3/8-Inch left hand drill bits.