Description This set of Hanson; Screw Extractors and Drill Bits provides the full range of screw extractors, both spiral and multi-spline, needed to remove the toughest bolts and screws from 3/32" to 15/16? (including metric sizes). The left hand cobalt drill bits are designed to drill into tough screws and bolts counterclockwise, which often helps to loosen the bolt while it drills. Features: Chart showing which drill bits and screw extractors to use to remove the most common sizes of screws and bolts. Six spiral screw extractors (Ex-1 - Ex-6). Sixteen sizes of Left Hand Mechanics Length Cobalt drill bits (5/64"- 1/2?). Thirteen sizes of Multi-Spline screw extractors (1/8"- 1/2?).