An external fixation system includes a clamp system configured to capture a fixation element. The clamp system has a first and a second jaw and a first and a second link attached to the first and second jaws that are configured to control the motion of the jaws. The links are arranged such that, when the first and second jaws are moved to a closed position, the action of trying to open the jaws is resisted by the position of the links, and to open the jaws, the links must be actuated.