Clamp (1) that can advantageously be applied to both temporary and definitive orthopaedic external fixation systems comprising: - a first coupling element (2), comprising a pair of opposite jaws (3, 4) together defining one or more seats able to house at least a first component of the orthopaedic external fixation system； - a second coupling element (8), comprising a pair of opposite jaws (9, 10) together defining one or more seats able to house at least a second component of the orthopaedic external fixation system； - an interconnection pin (7) passing through and connecting the first (2) and second (8) coupling elements along a main axis of rotation (x)； - fastening means arranged to bring the clamp (1) from a slack configuration, wherein the first (2) and second coupling elements (8) are relatively rotatable at least along the main axis of rotation (x), to a locked configuration, wherein the first (2) and second coupling elements (8) are relatively rotatable with each other； these fastening means dividing in - temporary fastening means, which can be manually operated, to temporarily lock the clamp (1)； - definitive fastening means, which can be operated by means of a fastening tool, to definitively lock the clamp (1).
