You know that sinking feeling you get when a bolt head snaps off as it snugs up? Well,these little grippers will lift more than just your mood. Sized specifically for smaller,more breakage-prone bolts less than 1/4" in shank diameter, they'll zip out the brokenshank faster than you can say thanks. Each extractor sports two business ends: one adrill bit for boring a hole in the shank, the other an auger-like extractor that binds itselfinto the hole and wrenches the bolt free. The self-centering drill tip prevents wanderingand allows a clean pilot hole - even on jagged surfaces. Kit includes extractors for thefollowing bolt sizes: #5 or #6 (M3), #8 (M4), #10 or #12 (M5) and 1/4" (M6).