This Drill Out Power Extractor kit from Alden features tools that are a drill bit and extractor in one, to make most broken bolt and screw extractions a snap. These products will not lodge themselves into the bolt should it resist extraction. This 7-piece set includes three regular Drill Outs, 5/16, 3/8, and 1/2-inch and 4 Micro Drill Outs, no. 5/6, no. 8, no. 10/12 and no. 1/4.