Insulated Allen Keys

A Hex key, Allen wrench or Allen key, is a tool used to drive bolts and screws with hexagonal sockets in their heads. The Allen name is a registered trademark, originated by the Allen Manufacturing Company of Hartford, Connecticut circa 1910

Originally named Allen Manufacturing Company, the business produced hexagonal set screws and wrenches to fasten them. The terms "Allen wrench" and "Allen key" are derived from the Allen brand name and refer to the generic product category "hex keys"