Remove nuts and bolts that are rounded off, rusted, or painted over. These extractors are made of high carbon steel with left-hand spiral teeth for maximum gripping power. The slim design fits into recessed areas and can be used with a socket, wrench, of Vise-Grip Locking Pliers. This set include 13 bolt extractors to remove damaged fastener sizes between: 8 - 19mm, (1/4" - 3/4")