A set comprising a coupling element, a first building element, a first building panel and a second building panel, wherein the coupling element is configured for assembling the first building panel and the second building panel to the first building element, wherein the coupling element comprises a primary coupling portion (2, 6) extending in a direction along a primary axis (Z1, Z1') and configured to cooperate with a first mechanical locking system of a first edge of the first building element extending along the primary axis (Z1, Z1'), to obtain an assembled state therewith by means of a folding displacement of the coupling element about the primary axis (Z1, Z1') to thereby lock the coupling element from displacement along a secondary axis (X1, X1') and a perpendicular tertiary axis each being orthogonal the primary axis; and wherein the coupling element comprises a secondary coupling portion extending in a direction along the tertiary axis and configured to cooperate with a second mechanical locking system of respective first and opposite second edges (21, 22, 21', 22') of the first and second building panels (20, 20'), characterized in that the second locking system is configured for locking the first and second building panels (20, 20') in a direction transverse of the plane of the proximal surface (25, 25') of the building panels by means of a folding displacement of the second building panel about its second edge; the second locking system of said second edge comprises a locking groove which opens in a direction along the tertiary axis in assembled state of the first and second building panels (20, 20'), said locking groove configured to receive a locking element of the second locking system of the first edge of the first building panel, said locking element extending in a direction along the tertiary axis; said locking element is received in said locking groove by means of said folding displacement of the second building panel about its second edge to thereby lock the second building panel and the first building panel from parting away in a direction of the plane of the proximal surface and transverse the second edge of the first building panel, and the first locking system and the second locking system are identical locking systems. wherein the coupling element comprises a primary coupling portion (2, 6) extending in a direction along a primary axis (Z1, Z1') and configured to cooperate with a first mechanical locking system of a first edge of the first building element extending along the primary axis (Z1, Z1'), to obtain an assembled state therewith by means of a folding displacement of the coupling element about the primary axis (Z1, Z1') to thereby lock the coupling element from displacement along a secondary axis (X1, X1') and a perpendicular tertiary axis each being orthogonal the primary axis; and wherein the coupling element comprises a secondary coupling portion extending in a direction along the tertiary axis and configured to cooperate with a second mechanical locking system of respective first and opposite second edges (21, 22, 21', 22') of the first and second building panels (20, 20'), characterized in that the second locking system is configured for locking the first and second building panels (20, 20') in a direction transverse of the plane of the proximal surface (25, 25') of the building panels by means of a folding displacement of the second building panel about its second edge; the second locking system of said second edge comprises a locking groove which opens in a direction along the tertiary axis in assembled state of the first and second building panels (20, 20'), said locking groove configured to receive a locking element of the second locking system of the first edge of the first building panel, said locking element extending in a direction along the tertiary axis; said locking element is received in said locking groove by means of said folding displacement of the second building panel about its second edge to thereby lock the second building panel and the first building panel from parting away in a direction of the plane of the proximal surface and transverse the second edge of the first building panel, and the first locking system and the second locking system are identical locking systems.