A clamp assembly for an external fixation system includes a first clamp member receiving a first elongated and a second clamp member receiving a second elongated member. The first clamp member includes a first fastener rotatably in a first direction to lock the first elongated member relative to the first clamp member. A second fastener connects the first and second clamp members. The second fastener is rotatable in the first direction to independently lock the second elongated member relative to the second clamp member. The first fastener is hollow and the second fastener passes through the first fastener.