Abstract: A coupling device for coupling structural members, such as panels, wall members and frame members, in edge-to-edge relationship. The device comprises a coupling member capable of cooperating with at least two edges to be connected to lock the same together and at least one coupling pin provided in each member to be connected, said pin extending longitudinally of an edge of said member and being spaced inwardly thereof. The edge is formed with faces forming chord planes of an imaginary cylinder whose axis coincides with that of the pin. The coupling member is provided with clip-on means for engagement around at least two adjacent pins thereby holding two adjacent edge faces in contact with each other, and fixing the structural members relatively to each other.