Throughout this site we use many technical terms, and given the breadth of readership our site enjoys, sometimes we are remiss and incorrectly assume everyone knows what we are referring to. For those that do not, here are some explanations of the technical terms use.
Piece of high tensile steel hexagon bar with a right angled bend. Either end is fitted into the socket in a hexagon socket head screw and used as a lever to rotate the screw. Allen keys come in a range to match screw sizes.