... , #3, #4, #5, 3.Usage:Remove broken screws,bolts,studs screw extractor setSize: #1, #2, #3, #4, #5,Usage: Remove broken ... screws,bolts and studs without damaging bolt or hole threads.Extractors have round flutes.About our company:Hangzhou Yifeng ... 1995.We specialized in manufacturing M3/M42 Bi-metal hole saws, carbon steel hole saws,kinds of drills(HSS drills, masonry drills ...