A rod with six sides and often L-shaped Used to remove certain screws and fastenings, especially set screws Sometimes called "hex wrenches" or "Allen key "
(Otomotiv) An L-shaped tool that works like a screwdriver, designed to remove screws with hexagonal holes in their heads. They are sometimes called hex wrenches
A tool consisting of an L-shaped bar with a hexagonal head, used to turn screws with hexagonal sockets. a tool used to turn an Allen screw British Equivalent: Allen key (Allen Manufacturing Company of Hartford, Connecticut)