Impact driver wrench

This hand tool is used to unscrew bolts that may have become rusted into place. One end has a 3/8th inch socket stub over which you fit with the appropriate socket head. You place this over the bolt and then use a hammer/mallet to hit the other end of the cylindrical tool while applying a slight twisting force on the the body of the impact wrench. The perpendicular motion of the hammer is translated (via a system of springs and prawls) into a sudden twisting motion at the head of the troublesome bolt. Since static friction decreases so much when the force is applied over a very short duration ---like the time it takes a hammer to smack the end of the impact wrench -- bolts that would otherwise require so much force that they might snap off can be easily removed.