The panels mm.600x600 clip-in concealed system are suspended from a metal adjustment snap type "TWIN CLIP" clip on the main supporting runner fireproof T section mm.24xH38x3600 with aluminium prepainted capping corrosioproof complete of punching slots for suspension hangers each mm.600. The "TWIN CLIP" concealed suspension system warrant the perfect and quick installation alternatives of the old very difficult system of the steel pipes.