General Screw extractors

Love them or hate them, they can be useful for some jobs. These above look much better than what were sold under the trade name "Easiout" (v.high carbon, not proper tool steel!) in times gone by, most of which remain buried broken off in assorted engine blocks and car parts.

In short - not for the feint hearted - as there are usually better ways of getting broken studs and bolts out... (See Techniques)